Can't get any friends in school.?

So, I basically just started 1st grade on something we call Videregående in Norway where I have extremely few friends but there are a lot of people. I have been going there for about a week at this point and I feel like I don't have anyone to hang with while I am eating lunch etc... I have like one friend who also doesn't sit with anyone or is in any group. Now this has become really awkward and boring at times as you can imagen. Now the thing is, I am not akward at all, I am good looking (to a certain extent), I am athletic probs one of the people with the most muscles in our grade which has like 200 people, yeah and as you can tell I have a certain amount of confidence, but I still make try to make the conversations revolve around others. BUT I FEEL LONELY AS HELL! Now I just wanna let you know me and my friend are two completely different people (except for the confidence part, he is cocky as **** lol) and he doesn't sit with anyone either. Now my question is. What am I supposed to do? Should I just not stress about it? Should I ask someone I don't really know well to sit with them? I guess I expected people to a bit more open you know.