How do i confess to my crush ?

So i am (16M) and My crush is (16F). I am silent how like to admire her. I get nervous when want to bring a topic up. I am more of logical person so dont know what to say to her . We go to the same institue and are in te same batch .Whenever i try to sit close to her I just end up getting nervous and start acting i dont know her. She also my academy rival

So, the people of reddit do you have any advise