Hope means that you want something in the future. "I hope I pass my test." Want is just you would like something. "I want to eat a cookie." Wish is similar to hope, but usually it is not used for yourself. You could say, "I wish that you pass your test." but not "I wish that I pass my test."

hope: to expect sth to happen or be true with confidence (maybe not hard to realize) wish: to expect sth to happen, although it's unlikely to come true (perhaps difficult to realize) want: to feel that you would like to have, keep, do something, or you need something (no matter whether it's easy or not)

I hope I can get a birthday present (very easy, at least, not difficult) <Subjunctive>: I wish I could fly in the sky (it won't come true, because humans can't fly)