You aren't born with social skills, you have to develop them. The only way to develop those skills is to actually practice them.
If you feel like you are under-prepared to do that IRL, there still is a way. You can use social games or online platforms. For me, that was VRChat.
I started after I finished uni. After a month I could talk to people for hours every day. I met so many great people there. I had to block a lot of not-so-nice ones too, but that's like 2 buttons per person. I can now unironically say "I have friends everywhere".
It's been 2+ months. Sometimes I feel like I have too many friends now, lol.
You won't only meet friendly people. You have to learn to handle trolls. My advice is to just block them or be disarmingly sincere.
Since people might not want to talk to a stranger, fill out your bio. Add your hobbies and interests.
Try to say hello to at least one new person a day. What's the worst that can happen? If they don't want to talk, they will forget you in five minutes.
Please remember, there are thousands of people just like you. Think how good it would feel if someone walked up and started talking to you. Be that person.
Sorry for my English, not my first language.
And also, if you have any questions, I'll be happy to answer them.