Youre going to have to try to get over your shyness. You are not going to make friends if you dont present yourself to people. That does not mean you have to be very outgoing though. You just need to make an effort to greet people, maybe ask them how their day has been going, and bring up topics you can both relate to(like the weather,or sports,or hot guys). An easy way of meeting people and making friends is by joining clubs at school. And it's easy to talk to people in clubs. After all, a club is a way for people to get together and talk about club-related things. And while youre in said club, you'll have a lot of fun!! Remember: don't be afraid to approach people :D

Don't worry about being rejected or looked at crazy. Most people wont brush you off. They're probably willing to make more friends, too. And if they do sort of hint that they don't want to talk to you, who gives a fuck? It's not the end of the world. Move on to the next person. The hardest part is simply initiating a conversation, but once you do, everything should go smoothly thereafter.

You also said you have a job. Do you have coworkers that are the same age as you? If so, talk to them. They'd be eager to talk to another coworker, since jobs can be boring at times. Ask them what school they go to. Talk about your work. Talk about random shit. They'll want to talk about things on their minds, too. Be understanding and be a good listener. I'm sure they'll talk your face off, son.

Good luck, PM me if you need more help.

*gets in a helicopter and leaves*

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Hi!