Datapack to spawn blocks in the world

Hello! I am needing some assistance with a small datapack I am creating.

With the fancy new 1.17 update at our doorstep, I thought of an interesting feature that Terraria players would appreciate. I want to make a datapack that spawns clay pots all over the caves, and once broken, they spawn a range of items. I have created my loot table in MCreator but there is one problem... I don't know how to spawn clay pots all over my world's caves. 

Any assistance would be fantastic!