Hey there
I'm in year 11 atm and I would recommend you to look at the syllabus and deciding what it is you want to do after school.
My teacher started our year with 'The body in motion' this topic is all about the bones, muscles, respiratory and circulatory system. It looks at the health related and the skill related components of physical fitness, aerobic and anaerobic training and the effect of exercise on the body. Biomechanical principles that influence movement where also studied (so motion, balance, fluid mechanics and force). I personally loved this topic
My first option was first aid. We completed a first aid certificate and learnt how to manage situations involving injuries and medical conditions.
My second option was fitness choice. This topic is about the meanings of exercise, different individual and group fitness activities, settings for exercise, the exercise as a commodity, motivators and barriers to exercise. My second favourite.
Last core was Better health for individuals. Now this is the one you are going to HATE!!!! Its basically year 7-10 pe boring. So meanings of health, different views, health behaviours of young people (so drug use, road accidents, sexual activity, lack of physical activity etc), factors that influence an individuals health, the control we have over our health, health promotion, Ottawa Charter. THIS TOPIC IS SOOOOO BADDDD!
Anyways PDHPE is a lot of content (more than biology in my opinion). It is very complicated, syllabus based and quite frankly full on. If you enjoy it, then it is lots of fun and interesting. I would give it a try and you can always swap in the first few weeks if you don't like it anyway
Hope it helped