Be happy without something you want doesn't mean you got comfortable.
To be happy without what you want for the future keeps you present, highers you vibe and make you feel more sure about your desire.
If you're unhappy with your actual reality you create an ilusion that only getting what you want will make you feel fullfiled, and we all know that sometimes we find out that this doesn't fullfill our soul the way we thought it would.
Accomplish a goal is an amazing feeling, and you should work hard, study hard, pray hard for it, but feel happy NOW.