Treat Foot as in "Foot the bill".

If you "foot" the bill, you pay it. To "foot" is an old way of saying "to total up" because the foot is at the bottom, and the foot of a bill, or total, is also at the bottom.

to foot (the bill)

It means to accept all charges and pay the bill.

Example:

"I need to take the dog to the vet to get fixed, but who will foot the bill since I am too broke to pay?"

Nothing. I suspect that you are thinking of "footing the bill" which means "paying the bill."