Idk what to do

So my bf and I have just started to get sexual, we haven’t had sex (I’m waiting till marriage) but he’s fingered me, etc. But me being my lovely innocent self, have no clue how to do something for him. I’m not stupid I’m the sense that relationships are give a little take a little, but he’s giving everything and I haven’t given anything back and he says it’s fine but.....I know he definitely WOULDN’T mind if I gave a little nut idk what I could do, as he understands my wanting to wait. But I honestly don’t know what I could do that would not lead to me losing my virginity (I’m better at controlling myself than him😂) So what could I do for him? I’m a teenager so my knowledge is limited...a lot😂😂😂