The edition used to answer the question is Twenty-Fifth Anniversary Edition--this can be important based given some editions differ in language.
That said, there are many important similes and metaphors found in Elie Wiesel's novella Night.
Metaphors: A metaphor is a comparison between two dissimilar things. Metaphors are implied, given they identify one thing as being similar to another in an imaginative or imagery-ridden way.
"An open tomb." In this metaphor, Elie is comparing the town of Sighet to a tomb. The majority of the Jews of Sighet have been moved out of the ghetto. As Elie looks around, the sight reminds him of what an open tomb looks like. Symbolically, this has a much deeper meaning: the town is dead, as will the majority of the people who used to live there.
"From the depths of the mirror, a corpse stared back at me." In this metaphor, Elie is comparing himself to a corpse. Physically, Ellie is emaciated and close to death. That said, many things have died within in, leaving a shell of what he used to be. The Holocaust changed Elie, dramatically. (This also qualifies as personification--given a corpse cannot really stare back at someone.)
Simile: A simile is a comparison between two things using "like" or "as" to make the comparison.
"The antechambers of Hell must look like this." Here, Elie is comparing the barracks the prisoners at the concentration camps are staying in to the opening to Hell. While Elie has no clue about how bad his life is about to become, he does recognize that it will be like Hell on earth.
"An assassin's face, fleshy lips, hands like a wolf's paws." In this simile, Elie is defining the head of his group as a predator. The comparison to a wolf denotes the leader as predatory and aggressive. As readers come across the other Germans in the novella, one can see the aggressive nature of them.