Trot him over them with a lead rope and teen try it ridding him
Thanks so much for all the ideas!
Lots of flatwork, maybe even lunging just to get him listening to you
I recommend at doing transitions in the canter. Also, I recommend doing a transition to trot to change direction. This helps your horse relax and not rush to do the change before you ask him. By being able to collect your canter and lengthen it you will be able to have more control jumping and at flying changes. A tip for flying changes is start of with a collected canter, then start lengthening it. This will make the flying change smoother for you and your horse.
It helps to take a circle before the fences, also another thing that helps is to work on slowing and speeding your canter in the flat. If he’s not use to lead changes try playing around with your speed then ask him to do a simple lead change.