Imagine that learning social skills from scratch is like tuning a feedback loop. You need to have something in the loop to begin with in order to tune it. If you're a child, good news, you can just feed your imagination's random number generator into the loop and see what happens. If you're an adult though, you might find yourself with absolutely no starting data on which to iterate, and your internal RNG has been forcibly shut down by growing up.
It's like trying to run Newton's method with NaN as your starting value, or like you're trying to follow a linked list, but your ->next pointer infinitely redirects to itself.
That's where I was at not so long ago until I realized that if you have no starting data, just copy over some data from your peers :)
Look at how others behave socially and start with those bits, it's not going to be easy but it is something to use until you have enough to bootstrap your own thing.
And remember even if it is weird, play along, things get better as you go. Keep making conversation (and always smile), it's better to be the awkward guy trying rather than the weird/silent/alone guy in the corner of the room :)
It's like trying to run Newton's method with NaN as your starting value, or like you're trying to follow a linked list, but your ->next pointer infinitely redirects to itself.