They knew everything. The Holocaust. The racism. EVERYONE KNEW EVERYTHING. Who says something else is lying. Just some facts why that's true. Many Jews has been Shot in public places. Jews had to wear special clothes and got beaten by soldiers and normal people. Also Concentration Camps were located in villages. You could hear screams and shots. Also many Jews had to go to work (forced of course) and their way were on normal ways. Through cities and villages. Also in Carneval they got themes against Jews and against Roma. Goebbels spoke 1941 in Berlin through the Volksempfänger (A radio. Everyone had to own one) that they have to kill the filthy race of the jew in Europe. It's a clear message. Also the "government" made movies nearly everyone saw (As an example: in Germany Avatar got watched 10 million times. "Der Ewige Jude" One of the famoust Propaganda movie in the nationalsocialism got watched 25 million times. By seeing this movie really everyone should've known. I'm German and I've speaken to "Zeitzeugen", who survived The world War. And they said it clearly. The main reason is why they're lying, because they have fear they get humiliated by another ones. They must have known. It's impossible. And the sad thing Is. They are lying. For 70 years not only other people but especially themselves.

Edit: I remember also a few things. They were rumors about what is happening in Poland like Ausschwitz. So maybe it could be true. 1943, when 50,000 soldiers made a break and went back to their family. They told everything then. The camps. The Holocaust. The rumors Became the Truth. It has been spread over Germany. But after the UK and USA and UdSSR just won they did like they were blind and deaf. That's the sadest part of all.

Second Question:

They were Protests. Just like the powerful Church protested against the Euthanasia of Crippled and disabled people, but here is another problem. They did not protest for jews or other groups. They only protested against euthanasia, because it included their own relatives or friends. Protests were of course some. Especially in the young public like students. The "Geschwister Scholl" are the famoust example. They've spread the Truth in the beautiful city Munich and mainly in the university. The Janitor was a proud Nazi and just told the SS (The Nazi Army, a powerful force mainly they killed Jews in Poland and Europe and searched for Traitors) Scholls got killed in public. And just to show they got killed by gouitine. The most people were in fear to say something so they just did nothing. The best would be to flee to the UK or Switzerland or USA. I hope I could help you.

Edit 2:

Also a protest was that Germany familes have hidden Jews in their houses. It was not enough and mostly they have been found by the SS and got killed.