I feel like a alien in a humans body

I want to talk with people so bad; make friends and hang out with people. But as soon as I do I suddenly feel sick to my stomach thinking about it, and after the fact exhausted and dreading the next event. Talking with people feels like a constant hunt for social cues I don’t understand, and trying to keep up appearances so I don’t look like a empty shell. Not to mention the fact that I don’t know how to properly make friends. It always feels like there is some kind of trick or thing I can say that means where friends now, but I just don’t know what it is, so I end up just making small talk and never talking with them again, even if I try to continue making small talk. Is it something I’m missing, am I just not good at talking with people? I haven’t had any major friends in five years and l’ve never felt so alone. It feels like I missed a lesion on how to socialize, and I’ve been trying to make up that each day, but still falling further behind. I don’t feel like I came from this planet, and I want to go home.