Oh okay, but if I was you I would still start basically from scratch
He was already trained to tack up and get on his back when I got him, but that's about it.
Start with join up and do lots of ground work and create a bond between you before doing anything with tack....take it slowly....as they say, slow and steady wins the race
The best way it’s with the help of a trainer/coach, with good experience 👍
I had to break in my horse and train it myself and YouTube lessons and getting somebody to video my rides was a life saver
Gymnastics and natrual horsemanship is amazing!
Maybe discuss with your trainer/coach?