Yep definitely needs rails/barriers on both sides so the tortoise can't fall off and flip. And making it a longer ramp would work also. But you might want to put your tortoise at the top and let him walk down it a couple of times to get him used to it after those modifications have been done.
@Pearly and @Yvonne G usually have better eyes. Anytime we see those ramped water bowls we recommend you get rid of them because they are flipping hazards.
I had a ramp less steep and my tort could not go up.
This setup looks like parkour for tortoises! Any chance you can disuse the whole top level altogether and just modify the hide to go on floor level in free corner? I think you and the tort would be much happier.
Reminds me of my little guy trying to climb the ramp I made for him when he was a baby. Made the rungs too far apart at first but he kept trying to climb it. Looks like a stairmaster exercise climber.
Do what everyone said above ^^ to keep your tortoise safe and make it easy for him to climb up. To introduce the ramp to him just place him on and watch him climb up, he will eventually come down and up again.
I would say extend it so it's not as steep, put sides on so he can't fall off but also put a layer is substrate on it too it might make him feel a bit more comfortable to go up it.