At secondary school you can study the main three sciences: chemistry, physics and biology. Important impacts in environmental science can be studied too.
Throughout your early secondary education, you will study these three sciences so you can cover important ideas. Then for your first exam choices in the UK, you have to pick a science. In later school or college, if you decide you really enjoy science then you can choose to specialise. Another option is to choose an applied science course which will have a more practical focus.