Germany was rebuilt after the war, which was mostly made possible by the US and whoever else paid for the Marshall plan (It's been a while since I did this in school, so I can't remember if it was just US)

The way WW2 went, Germany could not have won it. There are a lot of reasons for that, one of the biggest was probably that the country wasn't prepared for the war to get as big or last as long as it did.
Could Germany have won WW2 if WW2 went differently? Who knows? What was Hitler trying to win? What was the idea he had for the country, or empire rather. The better question would probably be whether Germany could have realised his ideas and plans.