Cave Generation (Ceiling, Walls, and Level)

Simply put, I am making a cave biome and I want the cave to have a ceiling of a certain block in that biome. I know this is already possible in Minecraft because of Lush Caves and Dripstone Caves, but I can not figure out how to do it in MCreator. I also want to know if it is even possible to generate walls for the cave as well. Ideally I would want the whole cave to be surrounded by one type of block. In the biome settings you can set a surface block, but there is no ceiling or walls option, leaving custom cave biomes looking like dogwater.

One more thing is the level at which cave biomes generate. I want to know if it is possible to generate certain cave biomes at higher or lower y values.