What if a boy has a crush on a girl he likes for four years and the girl doesn't respond?

It will get better gradually. It's up to you who has never been young and secretly loved. Growth is accompanied by such green youth. Secret love is also a part of youth. I don't think it's necessary to always get good things. I see you said that you are in high school, and it is estimated that you will graduate to take the college entrance examination. If you are still acquaintances and friends, then don't confess. At least there is a little less awkward space for each other. Even if you confess, you promise that if the university is not together, won't long-distance love be more painful? Time will erase a person's position in your heart, and you can't let it go. That's because you are too possessive. When you are attracted to something else, you will forget it. When you meet something better in college, you will really release yourself and your youth. Everyone who has been to college knows that you are embarrassed to say that you have been to college without having been in love several times. If this happens again in the future, think about the near future and the long term.