I relate to this a lot. Please try not to lose hope. I know it's very difficult, though.

"Even when im friendly and go up to randoms and chat with them at school they immediately get up and move away..."

I don't think this has anything to do with you. Based upon my experience, very few people enjoy talking to random strangers unless they're in certain places that are good for that, like an interest group, club, or social gathering of some sort. You might have better luck at such a place.