How to make a rat comfortable with its new home?

I bought a friend for my lonely pet rat Phineas. Anyways he was bred t be eaten by a snake i know cause i found him in the live food aisle. anyways he is living in a cage of his own by Phineas's cage, (Oh btw new rats name is Zeke) and he just stood there all day and barely moved. he only moved to get to his food bowl once. Is this because he is surprised and shocked because this is all new to him? Will poor Zeke die? How can i make him comfortable in his new home