Your computer is not authorised.
I wanted to download music on Apple Music but it says You must authorise this computer before you can play content saved offline on this computer. To authorise this computer, go to the Account menu and select Authorisations.
but I didn't find account menu also I searched but still can't find.
and I tried to find account menu on web and I didn't find
MacBook Air 13″, macOS 12.4