Help I’m desperate

Okay so my boyfriend and I have been adventuring I guess you could say in the bedroom.. we’re both 16 which I know is kinda young but eh oh well I guess but he did something last night that I really enjoyed but I don’t know if I could do the same thing for him... he went down on me if that’s what you wanna call it and it was great but I don’t think I could do that for him. I’m still new at all of this he’s the first I’ve done any of this with but I’m not his so he’s more comfortable doing things then I am. How do I prepare myself to do it or find a way to talk to him about it and how I’m not ready yet for that part.