Defiantly start with poles or low jumps. Do them until you feel bored going over them and you know you can do them with ease! Raise them up ( nothing major like a hole perhaps) and do that height till your bored going over them again. Keep repeating until your where you want to be! Also don't worry if things feel like they are going backwards, because sometimes the only way to go forwards is from starting from behind!
I have never been a big jumper ( literally) The highest I ever went was 1m and recently I’ve started riding again after a year. It’s been about two months with my new horse and we are only on 40cm. And I think we are comfortable there for a while longer. So I guess my advise would be to take it easy, no rush. Take your time and only move up in height when both you and your horse feel confident and comfortable xx