Straight guy needs advice

Ok so not gonna ask the whole am I gay question because I know that I'm bi curious. What I am wanting from yall is your opinion on a recent situation that has presented itself to me.I have a gay friend that I work with but we just recently started to talk more, by that I mean hey how's it going and we are FB friends now. He has invited to hang out and go do stuff like hiking and I love doing that stuff and I don't have anyone else to do it with. And he hasn't come off as trying to hit on me or anything, it's just like two friends hanging out.So my dilemma is I can't stop thinking about , ' what if something happens'. It's not that I don't want it to. I'm just nervous because nobody knows about my thoughts about other guys. But to be honest I can't stop thinking about being on my knees in front of him and pleasing him until he cums. I have never done anything with a guy before but I want to but I would hate to mess up a new friendship.I know this topic is kinda been beaten to death on here but I would appreciate any advice and or opinions.