Asked out for prom!! What do I do?

You should go! If he is your friend and everything you will have a great time. Anyway take a risk, would you rather stay home doing nothing while he is at the prom and could have been with you? And if you don't like dancing maybe he could show you how to dance to make the Prom funnier. Also, try to convince your parnets to let you go, it's your prom you shouldn't miss it for the world!