List events in order:

Eliezer and his father decide to evacuate with the other prisoners from Buna instead of staying in the camp.

Eliezer is moved to the construction kommando, and there is a selection.

Eliezer's father fails the first selection, but he passes the second, so he escapes the crematorium.

Eliezer, his father, and the other prisoners are marched through the snow to a new camp as the Russians close in on Buna.