Hi.
You stick out in social situations because you are withdrawn from them. If you want to blend in you have to be involved.

Easier said than done? Sure.

So what can you do? Start slow. All it takes to gain social skills is to take one step at a time.

First observe others. Look around at other peolpe and pick out qualities, personality quirks, things about them that you admire. Then try to emulate them. The more you do this the easier it gets.

Start with a smile and a hi. Practice on strangers. People in the store, on the bus, walking down the street. Quick interactions that build your confidence by repetition. Once you master that, then go from there. The best way to make people warm up to you and get their interest is to ask them about themselves. So get yourself a pen and paper and write down some questions that will draw people out. Then memorize them.