Get A Levels in Math, Physics, Geography and another subject you'd like to study.
You're 16, so you can already start your training towards PPL. But to work in a serious company a day, you need at least an university entrance level certification, so A Levels is mandatory for you. Keep studying, because the knowledge you will learn will be useful when you'll be studying ATPL theory.
Unfortunately, at my school (in Italy) I don't study Physics, nor Trigonometry. It will be a little bit harder for me, but nothing insurmountable
