On DeDRM it's not hard, [B]BUT[/B] original author has retired, you need the NoDRM version now.
Here's my latest guide RTFM of course, need help after just ask
[SPOILER=How To Remove The DRM From All Kindle eBooks]
[HEADING=1]How To Remove The DRM From All Kindle eBooks[/HEADING]

Plenty of posts here, and elsewhere that may go into more depth, but this covers the main details.
To remove the DRM from the Kindle AZW, AZW3, or Mobi files so you can keep the DRM free version forever.

Download the eBook with this version of Kindle, to get it with older DRM we can already easily crack.
[URL='https://archive.org/details/kindle-for-pc-1-17-44170'][B]kindle-for-pc-1-17-44170 – Amazon Free Download, Borrow, and Streaming – Internet Archive[/B][/URL]

[B]Important[/B]: You must use this version to download the eBook, if you downloaded them with a newer version, they have newer DRM
In that case, simply navigate to your [B]My Kindle Content[/B] folder (instructions after step by step guide), and delete the eBooks files.

[B]Very Important[/B]: Once this version is installed, you must stop it from ever updating.
Click On “[B]Tools[/B]” Menu
Click on “[B]Options[/B]”
In Options Widow Untick The Checkbox “[B]Automatically install updates when they are available without asking me.[/B]”

Files are saved using the [B]Kindle's ASIN (Amazon Standard Identification Number) Code[/B], which is shown on the book's store page, but only when the Kindle version is selected. It's always the first entry in the [B]“Product Details”[/B], but you will often have to scroll down to see the section.
[HEADING=2]Install Calibre[/HEADING]
[URL='https://calibre-ebook.com/download'][B]Calibre - Download Calibre[/B][/URL]
Download DeDRM plugin, you want the Full Release, currently it's [B]DeDRM_tools_10.0.3.zip[/B]
[URL='https://github.com/noDRM/DeDRM_tools/releases'][B]Releases · NoDRM - DeDRM Tools - GitHub[/B][/URL]

Extract the zip giving you two more zips ([B]DO NOT extract these, Calibre installs plugins using these zip files[/B]), and some ReadMe Text files.
[B]DeDRM_plugin.zip[/B] (Used to remove DRM from Kindle eBooks) [B]Required
Obok_plugin.zip[/B] (Used to remove DRM from Kobo eBooks) [B]Optional

Note:[/B] Occasionally only the [B]DeDRM_plugin.zip[/B] is provided, basic rules are
If zip has [B]_tools_[/B] in the name, extract, if it has [B]_plugin[/B] in the name, don't extract.
[HEADING=2]Now Run Calibre, And Follow This Step By Step Guide[/HEADING]
[LIST=1]
[*]Click on [B]Preferences[/B] Tab (Top Left Corner), go to step 2, [B]OR[/B] use [B]Ctrl + P[/B] keyboard shortcut, and go straight to step 3.
[*]Click first choice [B]Change Calibre Behavior.[/B]
[*]In Preferences Window, select [B]Plug-ins[/B] Button (Bottom Left Corner).
[*]In Plug-ins window, select Load plug-in from file (Bottom Right Corner).
[*]Navigate to where you extracted the DeDRM Tools, and select the [B]DeDRM_plugin.zip[/B], then click open button.
[*]Follow the on screen instructions to install, then shut Calibre down, and restart to make sure plugin is used.
[/LIST]
[HEADING=2]Drag & Drop From Windows Explorer To Calibre[/HEADING]
You can now use drag, and drop on the [B]*.AZW/*.AZW3/*.Mobi[/B] files Kindle saves to your Kindle Downloads folder, if you didn't change it, on windows the default is
[B]%UserProfile%\Documents\My Kindle Content[/B]
This path works in Explorer for the current user, whatever your user folder name is.
See this guide for other OS; [URL='https://www.epubor.com/where-are-kindle-books-stored-on-pcmacandroid.html'][B]Where are Kindle Books Stored on PC/MAC/Android[/B][/URL]

Calibre will now make a DRM free *.AZW/*.AZW3/*.Mobi file, that you can keep forever.
This works whether you buy the eBook, or borrow it using Kindle Unlimited.

You can even use Calibre to convert the [B]*.AZW/*.AZW3/*.Mobi[/B] file to ePub, or PDF, and many other formats, which is pretty much how every single Kindle eBook on this site is shared, they were almost all DRM locked [B]*.AZW/*.AZW3/*.Mobi[/B] files until they were DeDRMed, by the original uploader.

You can also use the Calibre eBook reader to read them in many formats., including the Amazon ones, and once the DeDRM plugin is installed the DRM removal is automatic, all you have to do is drag and drop them onto Calibre.

Even if you dislike Calibre as a eBook Library Management tool, like I do, because it ignores your own filing system, and removes those eBooks (Default scan Settings), it's still great at stripping DRM, converting to other formats, editing ePubs, and has a very good eBook Viewer.
[HEADING=1]High-Res Kindle Covers Downloads[/HEADING]
As an added Bonus you can replace <ASIN>, with the books code in these URLs, and obtain the high Res source covers Amazon uses to create the public facing scaled covers, these are usually even higher Res than the ones in the eBook.
[CODE]http://z2-ec2.images-amazon.com/images/P/<ASIN>.01.MAIN._SCRM_.jpg
https://m.media-amazon.com/images/P/<ASIN>.01.MAIN._SCRM_.jpg[/CODE]This works about 99% of the Time.

I've used this successfully even with eBooks removed from Amazon over a decade ago.
For those [URL=https://www.goodreads.com/][B]Goodreads[/B][/URL] is where I find the <ASIN> code.
It's still conveniently listed on the old site, the new “Beta” one you need to use the Amazon link.
A “Page Not Found” result, still gives you the <ASIN>, but Covers don't get removed, just the eBooks.

A better more detailed method, can be found using this Guide.
[SPOILER="Thonny Python Scripts + Calibre Hi Res Kindle Covers Plugin + Uhuru N’Uru’s eBook AIcons"]
[QUOTE="cognos, post: 245939, member: 3312"]
I wrote a little [URL='https://www.python.org'][B]python[/B][/URL] script that I run in (minimized) [URL='https://thonny.org'][B]Thonny[/B][/URL] that prompts for an [URL='https://en.wikipedia.org/wiki/Amazon_Standard_Identification_Number'][B]ASIN[/B][/URL] and opens a new web-page tab containing the Hi-Res cover

[CODE]
# Imported Modules
from easygui import * # dialog boxes
import webbrowser
import sys

while 1:
    Cover_URL = "http://z2-ec2.images-amazon.com/images/P/ASIN.01.MAIN._SCRM_.jpg"

    ASIN = enterbox("Enter ASIN: ")

    if ASIN is None: # User canceled
        sys.exit(0)

    webbrowser.open_new_tab(Cover_URL.replace("ASIN", ASIN))[/CODE]
[/QUOTE]
Using Cognos' Taffy Script as a Base, I've adapted it for three options, a combo Portal A+B variant, that tries both URLs at once.

Portal A+B variant has one downside, in that it opens both images, in new tabs when they both exist, which is the usual case, so it can get annoying.
[SPOILER="Python Scripts For Thonny"]
ASIN_Portal_A+B.py

[CODE=python]# Imported Modules

from easygui import * # dialog boxes

import webbrowser

import sys


while 1:

Portal_A = "http://z2-ec2.images-amazon.com/images/P/ASIN.01.MAIN._SCRM_.jpg"

Portal_B = "https://m.media-amazon.com/images/P/ASIN.01.MAIN._SCRM_.jpg"


ASIN = enterbox("Enter ASIN: Portal A+B Number")


if ASIN is None: # User canceled

sys.exit(0)


webbrowser.open_new_tab(Portal_A.replace("ASIN", ASIN))

webbrowser.open_new_tab(Portal_B.replace("ASIN", ASIN))[/CODE]
As an alternative, I've made two separated versions that, clearly indicate which portal is used.

[B]ASIN_Portal_A.py[/B]
[CODE=python]# Imported Modules

from easygui import * # dialog boxes

import webbrowser

import sys


while 1:

    Portal_A = "http://z2-ec2.images-amazon.com/images/P/ASIN.01.MAIN._SCRM_.jpg"


    ASIN = enterbox("Enter ASIN: Portal A Number")


    if ASIN is None: # User canceled

        sys.exit(0)


    webbrowser.open_new_tab(Portal_A.replace("ASIN", ASIN))[/CODE]
[B]ASIN_Portal_B.py[/B]
[CODE=python]# Imported Modules

from easygui import * # dialog boxes

import webbrowser

import sys


while 1:

    Portal_B = "https://m.media-amazon.com/images/P/ASIN.01.MAIN._SCRM_.jpg"


    ASIN = enterbox("Enter ASIN: Portal B Number")


    if ASIN is None: # User canceled

        sys.exit(0)


    webbrowser.open_new_tab(Portal_B.replace("ASIN", ASIN))[/CODE]
[/SPOILER]
Also I've edited the Calibre Plugin to search this new Portal B URL, I'll just show the relevant sources section here, and it's just the last line shown, that I've changed, otherwise the rest of the Plugin is unchanged.
[CODE=python]    sources = frozenset([

        'http://z2-ec2.images-amazon.com/images/P/{0}.01.MAIN._SCRM_.jpg',

        'https://m.media-amazon.com/images/P/{0}.01.MAIN._SCRM_.jpg',[/CODE]
You can also use the manual option as always.

The Thonny link is in Cognos post, it is required, so I've added link again here
[URL='https://thonny.org/'][B]Thonny, Python IDE for beginners[/B][/URL]
Using the Archives
[B]Thonny Python Scripts.7Z.001[/B]

This contains three files, and can be extracted anywhere, but I recommend your default Thonny User Scripts Folder.
If you extract the archive to your “AppData/Local” folder it will create the “Thonny/Scripts” folders in the extraction process, and you can then use the Environment Variable “[B]%LocalAppData%[/B]” to create Desktop Shortcuts, using these path names to the files.
[B]%LocalAppData%\Thonny\Scripts\ASIN_Portal_A.py
%LocalAppData%\Thonny\Scripts\ASIN_Portal_B.py
%LocalAppData%\Thonny\Scripts\ASIN_Portal_A+B.py[/B]

To “Run current script” in Thonny, press F5, or select the Right Pointing Green Triangle option from the toolbar, or from the run menu.
[B]Calibre Hi Res Kindle Covers Plugin [Zip].7z.001[/B]

This archive contains the Zip archive, that Calibre needs to import a plugin, so don't extract the contents of;
[B]Kindle.Hi-Res.Covers.v0.5.0-Updated.Portal.B.zip[/B]
[HEADING=2]Now Run Calibre, And Follow This Step By Step Guide[/HEADING]
[LIST=1]
[*]Click on [B]Preferences[/B] Tab (Top Left Corner), go to step 2, [B]OR[/B] use [B]Ctrl + P[/B] keyboard shortcut, and go straight to step 3.
[*]Click first choice [B]Change Calibre Behavior.[/B]
[*]In Preferences Window, select [B]Plug-ins[/B] Button (Bottom Left Corner).
[*]In Plug-ins window, select Load plug-in from file (Bottom Right Corner).
[*]Navigate to where you extracted the “Kindle.Hi-Res.Covers.v0.5.0-Updated.Portal.B.zip”, and install the plugin.
[*]Follow the on screen instructions to install, then shut Calibre down, and restart to make sure plugin is used.
[/LIST][/SPOILER][/SPOILER]