Life rule: when you tell someone a secret, it is no longer a secret. Do not be shocked if you hear it everywhere. Always expect it to become public information as soon as you disclose it. If you wanted it to be kept secret, you would have kept your mouth shut about your private matters.

On topic - most guys I know from high school did that. It’s very basic and horny teens do anything to appease their Hormonal Overlords. Both guys and girls.

Never hit first.

Friendships between men and women are rough. Even after years of a platonic friendship, there is always a risk one falls in love for the other, and not always the love is felt by both. At that point you can’t really be her friend anymore, as you are hurting all the time wanting more than friendship.

Telling her how you feel and the decisions you made are correct and you should not feel bad, as it is not your fault that you caught feelings and they hurt you.

Well, lying about that and driving his car which is illegal and in some countries it can get him in trouble as well, is a big fuck up. OP, stop breaking the law out of embarrassment. If you know how to drive then sign up and get the damn license.

Now go and start the long journey of regaining his trust.