Question I need help to check if the player is grounded or not

Okay so first of all, i use Bolt, which really has been more of a problem than help and i think i should stop using it. In my game i want the player character to be a square that kind of rotates, like a circle. Since when it rotates only the edges touch the ground but pretty rarely, jumping is awkward when moving. What is a simple way to calculate the distance between the center of the player and the colliders below? I tried raycasts, but i have no idea how to get them to work on Bolt, they always count as true no matter the distance i set.

 

I have no idea about Bolt, but I suppose its possible to use Layer Masks there? In that case exclude the Layer your player is using from the Raycast

 

I already tried that, but i literally have no idea how to use Raycasts inside of Bolt, since everything i find when googling is normal scripts! I want it to be a specific length and check if it hits the ground or not but the distance option didn't change anything, it literally seems to change only if i make it 0