I don't think we can say Hitler was a true white supremist because he was allies with "yellow" Tokyo, was heavily inspired by Indian culture and he had the German Wehrmacht train Indians to fight the British.
As for Germany winning WWII, it depends what you consider the turning point. If you consider D-Day as the turning point then, given the Soviet victory at Stalingrad and the destruction of German Army groups South and Centre, the USSR would have simply steamrolled over all German held territories.
If you consider Stalingrad as the turning point and the Germans won Stalingrad and eventually forced the USSR to surrender, then I think the USA and UK would have negotiated a ceasefire with Hitler, fortify the UK and the USA would have shifted their forces to the Pacific theatre. I also think the UK would have had a new lease on the life of its empire, telling its colonial subjects that they'd be better off with them instead of being eliminated by the Nazis. The UK would have made great efforts to industrialised India in order to mobilise its massive manpower. And then there would have been a cold war.