I am the only administrator on MacBook Air M1, but I do not have access to certain files.

When I attempt to open certain files, for example, my music library file, I receive the message "The folder cannot be opened because you do not have permission to see it's contents.". I am logged in as the administrator. When I open Finder and choose "Macintosh HD", I see the folders, "Applications", "library", "system", and "users". If I then select "users", I see the folder named "admin (Deleted)". The next folder is named "my name". I can see the sub-folders listed under "my name", and I have access to some of those folders. However, when I try to open other folders under the folder "my name", I receive the message, "The folder cannot be opened because you do not have permission to see it's contents." The only other folders listed under the folder "users" are "root" and "shared".

Can anyone tell me how to regain access to all folders and files?

Thanks!!