What should I do about this moron?

there is this guy in my science class that sits next to me and is SOOO annoying! I would be doing my work, for example, and out of nowhere, he’d be like “be quiet and do your work” then I’d be like “I didn’t say anything” and he’d be like “stop talking to me” and I’d be like “leave me alone, I have to do my work” and he’d be like “shut up.”

also, he like takes my pens or pencils, while I’m using them, then I have 2 like ask him multiple times before I get it back. he does the same to my friend who sits behind him. he wont stop talking to me, does he have no friends or something?

today, we had to do this science lab and me, him, and my friend were placed in a group 2gether and he did nothing while we did all of the work and the teacher came over and was like, your group is behind everyone else. I wanted 2 scream! he kept critisizing the way I did things and I was like “then you do it” and he was like “no, you can do it.” after we finished the lab, very nicely, as the teacher put it, he just recorded the results. he didn’t even help clean up.

he does this primarily to me, for some reason and says to my friend, who he also harrasses (but not as much), she’s so much fun to annoy…why is he doing this? I never did anything mean to him. I’m nice to everyone. what can I do about this?

(SRRY THIS IS SOO LONG!)