How did the end of WWII shape the postwar world?
The end of WWII dramatically reshaped the political landscape. The Allies split the European and Asian world between themselves. The USSR continued to control the northern part of Korea. Germany was split at first in four sections but France and England gave their territory to the United States as they attempted to rebuild their war torn homeland.
The USSR and the United States found themselves in a bi polar world; former powers (France and England) were shaken and lost much of their influence due to the costs of two world wars within one half century.
Countries throughout the world had to then choose their ally either the United States or the Soviet Union. This split between the US and SU was spread throughout the globe and would lead to the many events that are known as the Cold War.
The end of WWII shaped the postwar world by laying the foundations for the Cold War.
At the end of WWII, the Allies essentially split the world between them. In Asia, the USSR was allowed to keep the northern part of Korea. In Europe, the USSR was allowed to dominate the eastern part of Germany and the countries of Eastern Europe. By setting up this situation where the world was split up between communist and non-communist countries, the end of WWII set the stage for the Cold War.
There were other impacts of WWII, the main one of which was the fact that the US became the dominant economic power in the world. But this was caused by the war as a whole, not by its ending.