I find it so hard to make friends, talk to girls ans socialize in general... I always try to be nice, to talk and have a conversation, mostly with my classmates, but most of the time I just get ignored, or they reply just to be nice and then turn away. I don't feel like they're really interested on what I'm saying

Often, I also don't know how to join the conversation, and I find really difficult to even say anything. I also find it difficult to make friends on this very forum
I don't know what to do... I'm 18 years old and only had one true friend in my entire life, never had a girlfriend and never even kissed a girl. I just can't understand what the problem is. Is it because I don't have any talent/hobby? Am I boring? Stupid? Ugly? Or what?

I just can't understand... I really want to socialize with people, but I just don't know how... I don't even know where to start looking