To help with the overwhelm, If you scanned these important documents then I'm presuming you still have the (paper?) originals?
Treat them as your source of truth and work with them first - some might have superceeded your backups anyway.
Then, as others have said, follow the 3-2-1 principle, but keep one of the backups as plain and simple files (.pdf I presume)
If you lock the files in an app, you're making it even more difficult to restore them later.
Personally, I put my files (ie. .pdf, .jpg, etc) in encrypted online file storage (Hetzner) and I made sure I keep instructions elsewhere on how to get them back again (in case I'm... not able to)
Keep it simple
And + pfBlockerNG