Great question and I applaud your motivation and desire to know what you want at a young age. Please continue to learn as much as you can about your passion and stick with it.
Your question has a lot of answers...the best way I can think of to answer it for now is to offer you some resources and links to do some more research with - these all have to do with building an online business:
(please do not be insulted by "dummies" in the title if you have never heard of these books, they have been around for a long time and are all written by experts in their fields)
There are a lot of good resources online and in books that can help you reach your goal...stay motivated, inquisitive and try to learn as much as you can. Building a website these days is very easy and there are a lot of good companies that can help you build and maintain it.