How to get stronger wrist?

Whatever are the necessary parts you need to train for toproll?

Im 16 and ive been hooked in armwrestling since last year after one of my friends beat me. I used to be super weak and was recovering from a wrist injury i got when playing football. Ever since all my friends beat me ive wanted to get stronger and started looking into armwrestling and i got to know about devon, denis, levan, pronation, riser and more. ive wanted to get better at armwrestling but dont know how to train