iCloud & iCloud Photos · iCloud on the web, Windows and other apps
How do I get a copy of everything I store in iCloud?
Short answer: Use Apple's Data and Privacy page, signed in with your Apple Account, to request a copy of your data — iCloud Drive files and photos included. Apple prepares it over a few days; save the download to a drive with plenty of room.
Apple lets you request a copy of the data stored with your Apple Account, including iCloud Drive files and photos, from its Data and Privacy page (sign in with your Apple Account and choose to get a copy of your data). Apple prepares it over a few days and gives you files to download.
It's a good way to make an independent archive. Large copies arrive split into several files, so make sure you have room — an external drive is ideal. For just iCloud Drive, see downloading everything in iCloud Drive.