Jumping is REALLY fun.
But the one thing that can't/won't happen is anything "fast"
Learning to ride and train correctly is a very slow process. You should be able to stand in 2 point position @ w/t/c without stirrups before trying to train a horse to jump. As you will need extra balance to balnce a young/green horse. But don't give up you can learn together it will just take a little longer. Start with poles on the ground spaced about 4.5 feet apart-depends on horses size. Trot over until he doesn't balk or rush, stays straight and you can maintain your balance without holding on. Although if you need to hold on use an extra stirrup leather around his neck- much better than yanking the bit. Progress 3" height until you are 9" than make your poles into x-rails.
It would be best to work with an instructor, but if not. Balance-Balance-Balance