I know what I have to do but I can’t do it ffs

I know what I have to do to become more confident and make more friends, I have to go out and talk to people but I just can't do it. Everytime I go out and I see a group of people chilling and having fun and instead of going up and chatting up a conversation I just walk past them. It's like a wall in my head that I can't break through. How did you guys do it? I mean I know how you did it, you just did it but HOW?????