Sex advice.....?!?! Please..?

Well I'm 18 and still a virgin. I have never seen a guy naked which kinda makes me seem like a lame-o. I want to know if it hurts, how good it feels, and stuff about a. penis. What does a penis look like by the way? And is it uncomfortable getting naked in front of him or are you usually too in the moment to tell? Thanks for any information.