What does it mean when a guy stares at you?

So, there this guy who keep staring at me and we are really good friends. We have Theater together and he was also my scene partner. A lot of people thinks he likes me do to the way he texts. like he always sending me emojis and saying things like “ anything for you” “ love you”

and more. He always stares at me too and today i decided to wave when he was staring and he smiled. Even when he right next to he stares at me. I don’t know what it means and i just really want advice. Also, he my ex’s boyfriend close friend.