How to talk more in a group chat?

So my friend N put me in a group chat with her other friends J, T and O. I'm pretty good friends with N even though we've drifted apart alot in the last two years but we still talk sometimes, go to the movies, etc. I'm okayish friends with J even though we're awkward sometimes and I used to be pretty good friends with O last year. And I occasionaly talk to J. Anyways, N put me in a group chat with all of them and it's super awkward. I've only talked in the group chat about 2 times. They're always talking about inside jokes, homework and stuff like that since they're in the same class and I'm in a different class. They also always talk about their interests like anime, Minecraft and things like that which I don't mind but the conversation never seems welcoming to me since I don't relate to what they're talking about half of the time? What do I do? How can I slip into the conversation?