Some recommendations:
I tried to watch
Instrument the other day, the documentary about Fugazi. It's on YT, but the quality is only 240p. I don't want to waste my ears on it, but you're still young so you probably won't mind as much
.
The same guy that made that documentary, Jem Cohen, also made this:
Empires Of Tin. It's a registration of an art performance in Vienna about the WOI, with live music from artists like Vic Chesnutt, Silver Mt. Zion and Guy Picciotto. This quality on YT is also not HD, but 480p is watchable. It's a favourite of mine, but I love those musicians.
If you like Bob Dylan, watch that Netflix documentary about the Rolling Thunder Revue.
Oh and This Is Spinal Tap ! Probably the best documentary about a band ever made
I'll watch that tonight, long time since I saw it.
(Bummer, I added a YT link for that movie but it's a fake, so removed it again. But try to find it if you can)