Hi! That's a very broad question you've asked; are there any specific parts you're more interested in? The subreddit wiki has a lot of good questions about Nazi Germany and WWII that've been answered in the past, or you could search the subreddit to find even more. If you're interested, the books and resources list has a lot of good recommendations too.

To give a general answer to the last part of your question - No, Jews did not originate in Germany. They originated in ancient Israel, wrote the Tanaakh (more generally known as the Old Testament of the Bible), and many were exiled by the Roman Empire after repeated rebellions. The subreddit wiki has a lot of past answers about their history and persecution through the Middle Ages and early modern period. Hitler fanned the flames of a longstanding and ignominious tradition of antisemitism.