There are two available Walker statues available in Goat Simulator:
Both are located very close to the spawn. For the first one, go into the house, up the stairs and go into the dark green bedroom. Headbutt the dresser to knock down the small statue. Now go back outside, into the front yard and use the trampoline in order to throw yourself into the nearby treehouse. Hitting the treehouse should break some of the wooden beams, causing the other statue to fall off, gaining the achievement.