The Underground Resistance Network fought the Nazis. They did a phenomenal job too. In Italy they fought them overtly. The French Resistance did that too and took Paris back themselves once the Allies landed. The other countries had to conduct covert methods of conducting actions against the Nazis but that was needed badly too.
The Poles were invaded by the Nazis. They did not want to fight with the Nazis or cooperate with them. Poles were killed by the thousands. Germans moved right into their homes and businesses. So any Poles who made it to freedom or were already in England they fought as free Poles with the Allies to defeat the Nazis. There was a fairly strong Underground Resistance movement in Poland to fight against the Nazis.
In the context of World War 2 resistance groups resisted the Nazis.
Anne Frank did not fight the Nazis, she hid from them.
The resistance groups used sabotage, strikes, demonstrations and assassination to try and over ride the nazis. If caught doing this they were harshly treated by the nazis.
To distribut cupcakes and candy to the Germans while dispensing bullets and hand-grenades to the Jews.
The Resistance in France & elsewhere in Europe did very valuable work against the Nazis. Many Allied airmen, shot down over Europe were helped to survive and some returned to Britain to continue the fight. The work of the resistance was vital in the run up to D day.
When they invaded, the danish people didn't really put up a fight( of course there was a Resistance though). After the invasion the Nazis went from building to building searching for Jews to exterminate.
There were no religious resistance groups that fought against the Nazis. Leaders of most major religions not directly targeted by the Nazis were actually pro-Nazi, such as the Catholic Church and numerous Imams and Muftis in the Middle East and the Balkans. The Orthodox Church opposed the Nazis in principle (since they had defeated Greece and attacked Russia), but did not advocate resistance to the Nazis and did not defend the minorities attacked in the Holocaust. The resistance groups that did organize were nationalists, socialists, and partisans in any given occupied area.
Have a look at the related question.
The organizations that fought the Nazis in secret were collectively called "the resistance" or "the underground."
The Resistance fighters are people who helped the Jews fight the Germans.
The Nazis