Check the sidebar and find the “modlog” link at the bottom, just above the list of mods - the link will differ for each instance so I can’t give you a direct link.

The problem is that music isn’t generally FOSS - people would like to be paid for their work. So the next best thing is to set up your own music service where you can add your own music.

Here’s a good discussion: https://www.reddit.com/r/selfhosted/comments/rdxbxp/is_there_any_spotifylike_selfhosted_music/