Easiest way to make a ringtone under iOS 26?

Hello,
I bought a song today, which I wish to use as a ringtone.
Acording to some reading I've been doing online, there is a bug in Apple music, where if you use the, "convert to AAC" option, the new version will not show with its shortened time.
Rather, it continues to show the time of the full song.
Does anyone know the easiest, most accessible way to create a ringtone in iOS 26?
Someone suggested i try GarageBand which I have installed but I can't figure out how to access my Apple music library from there.
Any tips would be greatly appreciated.
If at all possible, i'd like to do it today, as the song title contains today's date.