You could join a room, introduce yourself and play some of your music. As long as you aren’t spammy with it, people won’t mind. It really isn’t designed to promote yourself though.

You could also join the discord for RVRB, there is a channel there for self promotions!

Sure! If your music is on Spotify you can add it to your queue and play it here. Some rooms have their own rules about self-promotion but its not disallowed! We love to hear new music.