Describe how Crooks differs from other ranch hands, and what does Crooks say will happen to Lennie if George doesn't come back?

Crooks is different from other ranch hands because he is black, has a room to himself, and he has possessions. Note, he was injured by a horse which has damaged his spine and isn't welcome in the bunkhouse because of his race.

Crooks vision of what will happen if George doesn't return.......

Crooks bored in on him. "Want me ta tell ya what’ll happen? They’ll take ya to the booby hatch. They’ll tie ya up with a collar, like a dog."