It’s great that someone as young as yourself is looking ahead to the future, but take things one step at a time. What education options are realistic for you, financially and in terms of location? There are several universities in the UK that offer good CG courses, but you may also want to consider getting a degree in something that isn’t specifically CG, but related and beneficial, like art or programming. This is simply because CG is a pretty unstable career choice, so it is worth considering investing in an education that could have application elsewhere, should you need to rely on that. Alternatively you could choose to go down the self-teaching route, but considering the way the industry is changing, I’d personally recommend that youngsters get some kind of formal education these days. It’s just a safer option, provided you can afford it, without taking on huge student debts.
In the meantime, considering your age, you’re at an advantage, as you have several years before you’ll go into higher education, which gives you a lot of time to develop your skills. Don’t worry about the job market and experience and all that right now; focus on learning and preparing for your education further down the line.