Help making a very simple datapack, im confused.

I don't have any clue on how to make datapacks but I think im doing something very wrong. Im trying to make a datapack that scans every stone block in a 500 x 500 radius from 0 0 and make it destroy every stone block that is touching 6 other blocks (fully surrounded, not including air). When I do /datapack list it shows up but none of my function commands work. Someone please help 🙏🙏🙏.