I am a 15 year old army cadet and thinking of joining the army but im not too sure what path to take,what do you do?

Hi, what a great question and a really tricky one too! My advice would be, think about what you like doing - are you into fixing things, or computers, or just being physical. Do you like working/being with people more than you like sitting by yourself. All these things will start honing the different types of jobs you might like (whether that's in the army or not). In the army there are around 77 different trades - chef, musician, driver, port operator, postal courier, ammo tech, armourer, UAV operator, vehicle mechanic, avionics technician, cyber engineer, HR specialist, medic, geographic engineer, nurse etc etc - depending on the quals you get for GCSEs and your score on the army psychometric test everything is open to you.
To complicate things you might also want to look at the officer route rather than soldier route (again, depending on your quals and if you intend to stay in education after GCSEs). You might want to look at joining the Army at 16 (after GCSEs) and going to Army Foundation College Harrogate as a Junior Soldier. Have a think about what you like, what is it that drives you, what subjects do you most enjoy at school and let me know. Perhaps then i could give you a bit of a steer and you can go away and do some research in different areas. Really it is research. Speak to your staff at cadets (if any were in the Regular army) and they might be able to help or at least have some contacts for you to also speak to. Good luck.