1.20.1 Reverted Caves

So I'm currently on a mission to make an "Alternate Adventure" of sorts for Minecraft. To get beta features used in Minecraft 1.20.1, I was able to utilize "modern beta" mod packs to simulate a classic but familiar experience. I want to get rid of the features that made up the Caves and Cliffs update, reverting ores veins to their original y value range, bedrock level being y = 0, and the usual. I'm struggling to figure out how to do this, because the limitations of MCreator, even when writing java functions, seem to be a much larger barrier than I had imagined. Can I get some tips or suggestion help in this?