The researchers set about finding other survivors. After a few days, they have found nearly 200 others, from surrounding cities. Almost all of them, after having labored under an oppressive rule for all their lives, are more than willing to join with the Republic of Russia.

Together, they begin to rebuild the city, building by building, reworking the rubble into completely new shelters when it is too damaged to reconstruct.

Most of the survivors still have PPSh-41 guns (and similar designs), which had become common in most households when the war began. They discover a forest a few miles away from the city, which will serve as a hunting ground until they find a reliable food source.

But he did in the original post, saying Germany was completely destroyed and uninhabitable.
Kydon: thanks, I changed AK-47 to a more realistic model.

A few scouts from the Republic discover an abandoned iron ore mine, complete with intact smelting equipment. With access to iron and ironworking facilities, production of shelters speeds up considerably. 

Um i'm new here..but i just read that and he said that there was a war between North America and Germany...but he said nothing about it being a deadzone or completely destroyed or anything in the original post so how could Kikkin had of known?

It said North America and Europe were destroyed; Germany is part of Europe (in fact, probably the hardest-hit area).

The Republic now has fully-functional shelters, and the original founders (termed the Directors) have resumed using their bunker for living space, and other bunkers across the city are also being occupied, as a means of escaping the cold. 

Rudimentary coal-powered heating systems are built and installed.