Custom World Gen

I was here long time ago and my plans haven't change. Sometime ago I wanted to create a super flat world that would be with sand and deadbushes only with structures. I did it.
But now I feel like superflat is kinda boring and I want to add some height. I want to add some perlin noise kinda thing and that's it.
Sadly my datapack was for older version and since 1.21 adds so much stuff I want to focus on that version.
It's kinda like expansion for a map from planetmc Deadbush Lands
Villager, Sticks Sand. Trade with villager and beat the game