I don’t want to be an incel anymore

When I was younger and more insecure, I would just go out and talk to people and make friends and it was so easy. But after being brutally rejected by this one person I really liked. I became socially inept because the anxiety of being rejected again made me overthink things more than ever. I wanted to fix this so badly and I wanted to try and get back to the person I was before. What’s the best way to start?