How to kindly tell someone from school you that you’re no longer interested after the first hang out?

I (F18)met this boy (M17) recently and we had been seeing each other every day for a couple weeks because of our class schedule. At first I found him a bit attractive. And after some chatting through instagram we decided to go to the movies a couple days later. But I kind of rushed things because I wanted to know how he is like in person, and I made an excuse saying we can grab food and talk about school stuff, and we hung out the entire afternoon yesterday. After the hang out I realized we barely had anything in common and basically the vibe wasn’t there, but today when class ended he kind of followed me and my friend (which she kind of know him, had a brief chat), to walk around. When we were about to part ways I mentioned that I wanted to go to the library alone and he followed me as well, and we ended up hanging out for the entire day also. How do I make him lose interest in me/ stop following me around without making things awkward?? We still have a movies to go to tomorrow, that’s so awkward.😬 Also, none of these hangouts are planned in a romantic way, how do I twist it into like im just going out with a normal friend? It’s even worse because he had never dated before.