Usually this would be easy, but I'm more used to using command blocks as opposed to function files. It would involve /execute, and /testforblock, I assume.
#running a command *if* there is a block directly underneath a player
fair yoke
For the sake of simplicity, running /say Hi if a player is standing above a diamond block
mint sigil
execute as @a at @s if block ~~-1~ diamond_block run say hi
fair yoke
Oh thanks!
small sparrow
Usually this would be easy, but I'm more used to using command blocks as opposed...
You can use this to test if they are standing on any block
/execute as @a at @s unless block ~~-1~ air run say I'm standing on a block