I get you, kid. It does seem pointless. It does seem worthless. And honestly, it seems pretty fuckin simple. But you're right. Studying in't about what you want to do. Hell, it ain't even about what other people want you to do. People have been perpetuating this paragon of studying and hard work, that they've forgotten what it's about. Everyone except the people who know how to use what gets churned out by the system. What you get taught in school is simply how to use the greatest tool that will be available to you for the rest of your life: your brain. They will teach you how to to think efficient thoughts, create and communicate creative ideas and handle immense amounts of mental and emotional strength. The fact that they force everyone to do it kind of devalues its worth at the end of the day, though. 

You don't have to be motivated to study. You've just gotta be motivated to use your head. And honestly, nobody but you controls how you use it. I once felt that motivation, the joy of learning. But that stifling environment does get to you, eventually. You can choose to be stifled, or you can use your mind for whatever the hell you want. There are a lot of problems in this world that can be solved much faster, easier and less painfully with the use of your brain. You haven't encountered those problems yet. But if you trust the word of a stranger, trust that when you encounter those problems, outside of your school, outside of your workplace, outside of your parents' demands and control, you'll find that you hold one hell of a weapon that can be sharpened very well against the walls of this prison you find yourself in. You just gotta work against the boundaries, and you'll have the tool to go up against the people who built them.