How can I initiate sex with my friend?

I (18F) and my friend (18M) aren’t in a relationship but it is obvious we have feelings for each other. He has been with plenty of girls, however I on the contrary have only been in one relationship. He has made it obvious he is interested in me on numerous occasions, but hadn’t done anything about it. We have been friends for a really long time and I think he just doesn’t want to ruin our friendship by entering a relationship. Recently however, he kissed me, and we made out seriously, he began unbuttoning his pants and took off my shirt, but I stopped because I had only had sex once before and I wasn’t ready. He didn’t say anything and just left. I called him a few times to see if he would meet up. Eventually he said he would go to lunch with me and just talk. I really regret not going all the way with him, and now I’m waiting for him to arrive at lunch, I want him so bad but I feel like I ruined my chance. Do you have any advice or help?