San Angora: Become Human Achievement in Goat Simulator 3

This alternate character is unlocked on Libertarian Island in the northwest corner of the map. On this island, you'll need to go to the southeast corner of it, where the rocks form a cliff that overlook the water. There's a cliff platform that goes around the side of the island you can walk on. Down there, tough to spot from above, is a rock cave entrance blocked by a boulder. You need to baa at the boulder and it'll be removed. Head inside and down, and headbutt/lick the human to become him and unlock this achievement. Location pictured below.