how do i improve my relationship with my boyfriend?

Well my boyfriend Roman and I are quite close but we are still kinda young so we don't have much freedom yet so we only see each other by visiting every few months and we are both VERY shy kissers...the few times I actually kissed him he kinda freezes and when our relationship started I didn't realize how sensitive it is and so I kissed him often and he always froze and had a clear expression on his face and we never act like bf and gf usually anytime we do it's only when we are in a really good mood but that's quite rare.and I kinda want to improve our relationship between me and him so it will stop being kinda awkward and we stop acting like new friends and start acting like a couple and I also want to have a future with him any ideas?