Try eating with a group of people at lunchtime, even if you don't talk to them much. Listen to what they are talking about, so that you can understand the topic and start talking about it too. I don't know your age, so regardless of it, just do what those people do so that they won't really think that you're boring. Even I experienced that a lot of times before, so I tried to join them and talk with them, and it actually worked. It takes some time, but you will finally realize that you will have friends in the end.