First: you can't make someone love you, any more than the doll on the store shelf chooses its owner. The age when girls think they can make someone love them is about 12-14; after that, they learn love is more complex and you have less control than you wish or think. There may be a Freudian reason why girls go thru this (look up object choice theory), but it's a common and age-appropriate misconception. Second, what you can do is be the best choice among the many he has, and stand out from the crowd in some way. Be around him, spend time with him, be positive and appealing, and see how he responds. Let him make a choice, and then be ready when he makes it. You can't make it for him, and if you could, it's not love.
You can be able to tell if a guy likes you by the way he looks at you, his body posture and how he behaves when you are around. Notice if he flirts with you or likes to appear in places you least expect him.
Watch the way the way he looks at you. Does he abandon his friends just to talk to you? his posture and physical looks give some of it away. Is is hair more styled? is he more fashionable? does he smell good? if these improvments have happened it might be that he likes you. Try flirting and talking to him a lot! if you dont already, get his number and text him! if you dont know who he likes, then ask one of his best friends! or someone who knows him well!