music procedures for boss

To the point, I just want music, to play when a boss spawns (via an item, or commands, whichever is more doable) via procedures (if even possible), and to stop when the boss is no longer alive.

maybe, if possible, at all, the music follows the boss. I don't know if that is a thing that can be done, but yah know, might as well ask here as well.

version 1.17.1(the latest at the moment from what I saw it could do)
And again, boss spawns, music starts, boss dies, music, well, dies as well lol.

I can get the music to play when I click with AN item, but there is NO way I can see to DESIGNATE a SPECIFIC item that needs to be right clicked, otherwise I'd just use the spawning item I made for the boss.

I also can't seem to make it specify what ENTITY is required for the boss to spawn, as it just starts whenever ANY entity spawns, and if I do entity joining the world, it just spams it whenever an entity starts existing...

I honestly just want music to play when boss is alive, and to stop when it's not, I feel like it shouldn't be this hard to make that a thing, but I MIGHT just be blind and dumb, lol.

thanks for taking your time to read this nonsense lol.