If I look at the quote you wrote why your parents have not supported you in that matter because at your age, your main task is to focus on education first, not investment, if you are old enough and have a permanent job later I think the decision is absolutely in your hands and you only need your parents' blessing by conveying that you have started to enter and invest in BTC. Rest assured, no parent doesn't want to see their child succeed in any situation.
Reading through the posts under this thread, I noticed how everyone is applauding the Op for taking the bold steps by wanting to invest in bitcoins at all costs. It's a good move actually but I like the way you reason. A child of such age should not budden themselves with investment when they are supposed to be serious with their education. Children can be be very influenced and we know how panic investing in crypto can be even for grown up adults. There's no reason to rush investment, it's good to start early though but we shouldn't overlook the consequences too.
If you really want to make your life better and you have money to invest in bitcoin and you have tried your possible best to convince your parents and refuse to understand the impact you are trying to bring in to them, and you have your own money, I don’t think it is necessary to wait for their approval before you will invest in bitcoin, since it’s your personal money and not the family money.
The fact that he's trying to seek for parents approval shows that he's still a boy who's under the control of his parents. An adult who who can take decisions for himself doesn't need approval before investing in whatever he has knowledge of and think can yield him profit as long as the money to invest is completely his own. It's very rare to see children of that age independent, they are still under the care of their parents. They also want the best for them but they're being protective knowing that they have no full knowledge of what they're doing yet due to their age.