I suggest trying to have a serious talk with your parents about going to a public highschool instead. I switched to a public highschool for my last two years of highschool, and I'm very glad I did. It was just as full of pricks as public highschool, but they were less annoying kinds of pricks.
The work was so much simpler than in my catholic highschool that I was able to get great results on all my final exams without even trying, plus i got to anjoy going to highschool instead of hating it. I think the great results i acheived outweighed having to graduate from a public instead of private highschool. There's certainly nothing wrong with doing it.

I don't think dropping out of highschool is a good idea. It doesn't reduce your opportunities for the future [there are plenty of other ways to get into just about any university degree]. The thing is, it's easy to get more kinds of jobs, and easier and faster to get into more kinds of courses, if you finished highschool. You may think you know what you want to do right now and that it would be pointless to bother finishing highschool, but the fact is that most people at yor age, and even a lot older than you, end up wanting something completely different than what they previously expected. That includes the ones who are very very good at assessing themselves and what will or won't make them happy. So no matter how sure you are you just want a wage job or whatever, acting on that thought will put you at a huge risk of having at least a slightly more difficult time getting what you want in the future.