If you have read this book, you will note that Anne Frank gives a poignant account of what happened to the Jews in not only Nazi Germany, but all over occupied Europe. There is an excellent study guide of the book here on eNotes at the link below that summarizes the plot to help you in writing your essay.
What the Nazis attempted to do with the Jews, at first, was to round them up and segregate them into ghettos, such as the infamous Warsaw Ghetto in Poland. This was how they could control them and eventually deport them to the Concentration Camps, where they were turned into slaves and then gassed. In Anne's diary, she tells of how she and her family had to leave Frankfurt, Germany, where they lived, when Hitler took over. They escaped to Amsterdam, Holland, but when the Nazis invaded Holland, they had to go into hiding there. In any country that the Nazis invaded, they first segregated the Jews into ghettos, and then shipped them to the camps. Many, many brave Europeans tried to hide the Jews, such as Miep Gies who was the one that eventually found Anne's diary. In Denmark, when the Jews were ordered to be arrested and deported, the brave Danes arranged for over 8,000 Jews to be evacuated to Sweden. Almost all the Jews in Denmark escaped the Holocaust because of this.