The Indians taught the first European settlers the value of a buck.
Like gold, deer or buckskin was used in trading as a unit of value against which everything else was assessed.
That’s how a dollar was called a “buck”.
The phrase, “The buck stops here” is a different story altogether.
That expression came from frontier poker, in which the buck was a knife made of buckhorn that was passed around the table to indicate who was dealing.
When a hand was finished, the dealer “passed the buck” to the next player.