Sex help

Okay so me and my boyfriend are very open when it comes to talking about sex, and I asked him what he likes that I do and he says he likes everything but at the same time I don’t do much? I just “lay there and grip the sheets really tight” but in my defense he is VERY big (if you know what I mean) and it basically makes me go stupid and weak whenever we have sex. I want to see if you guys have any suggestions as to what I can do more? Like I’ll try to sit up and kiss him during but he’ll just push me down and go to town so I don’t really know what more I can do..? Help