Can't access local Documents folder, only iCloud one
In Big Sur the real location of an iCloud Documents folder is within ~/Library/Mobile Documents. There you will also find folders for various apps that maintain their own iCloud folders. No matter where you view them from, various icons should appear by files (to the right in list &amp; columns views) to indicate their iCloud status. The full explanation of those icons can be found on this Apple Support page. Here's a screenshot from it...