Is it easier to learn to skate on figure skates or hockey skates?

Neither, really. It mostly depends on what you decide to start with. People who skate in hockey skates generally fall over on the toe picks when they try figure skates, and even accomplished figure skaters say they feel like they're gonna fall over when they put on hockey skates. So it's pretty subjective.

One thing I can say from personal experience, figure skates encourage much better posture and skating technique than hockey skates, as figure skates require you to straighten your back out much more to skate in/not fall over on the toepicks in them compared to hockey skates, I started in hockey skates and switched to figure like a week ago, so yeah.

The only bad part of figure skates is, if you get a higher end pair to just start out in, the toe picks will be close to the ice, so if you lean forward much at all, you'll fall on your face. The other issue is, up to about the 80s, figure skates were made of a single layer of leather, that you could move your ankle around in, like a combat boot. I find these really really hard to skate in, due to the lack of ankle support, compared to hockey boots. I'm sure if you start in them, you can eventually get used to them, but after starting in hockey skates, I could not at all. However, newer figure skates are as stiff/stiffer than most hockey skates, so that's no longer an issue, but I'm just saying this if you find some cheap $20 brand new Chinese "figure skates" or find some older skates at a garage sale or something.