The built-in iOS Files app cannot create or natively extract split or multipart ZIP archives (.z01, .z02, .zip.001), though you can open standard single ZIP files on your iPhone or iPad. To handle multipart split archives, you must use a third-party file manager from the App Store.
Managing Split Archives
Third-Party Apps: Download an advanced archive utility like iZip, Keka, or Unzip Tool from the App Store.
Extraction Process: Share or move the split volume files (.zip, .z01, etc.) into the third-party app's folder via the Apple Support Files guide, then trigger the extraction from the primary file (.zip or the first part).