I love a girl in my clroom .. how to tell her I love her , help please , explain.?

I am 16 , I am at 10th grade , I love her soo much and I wish to live with her forever , I always look at her , she looks too but I don't know how to tell her I love her , also I am scared that if I tell her I love her she will break my heart . When I talk to her I feel that she wants to end the conversation , I don't know bec she hates me or she is shy . Help pleaseee