I know MIR asked for responses that aren't sarcastic, but this is really the only absolutely necessary change for Germany to end WWII in a favorable position. The man was a total nutter. It may be a myth that the generals could have won the war if he just trusted them to handle it, but it's certainly grounded in a factual basis.
Take Barbarossa. Hitler insisted that the Wehrmacht take and hold Leningrad, Moscow, and Stalingrad simultaneously. This is a massive operational area. The generals more modestly proposed taking only Stalingrad to cut off oil from the Caucasus and holding the line there while the Soviet army slowly starved itself of fuel. Alternatively, it was proposed to take Moscow, as the hub of Soviet railways, and accomplishing the same end.
Hitler insisted that the Wehrmacht take and hold Leningrad, Moscow, and Stalingrad simultaneously, because what Mein Wildemensch wants, Mein Wildemensch gets. This was a suicidally bad plan that disregarded all practical concerns.
And it still almost freaking worked! The Wehrmacht performed better than anyone, except Hitler and a few of his sycophants, could have reasonably expected, though in part because Stalin opted for a retrograde maneuver. If Fuhrer Cuckoo Bananas hadn't been in charge, it's plausible that they could have taken Stalingrad, established a defensible line, and held off the Soviet counteroffensive. At the very least, they could have prevented the catastrophic defeat that it turned into.
Germany doesn't have to conduct a physical invasion like Sealion (not even possible in the first place) to make the UK drop out. Just bomb them for a long time or go peaceful and play the diplomatic card hard and seek some sort of truce/peace. A stalemate against the world's largest empire is not bad, eh ? And it gets even better if it gives you a free hand in the east
This was London in 1940, looks like Germany in 1945.
That was pretty much the Nazi plan to deal with the UK. Churchill would have none of it. It might have worked if they had kept it up for three years or more without the US joining the war or if there had been no invasion of the USSR, but bombing isn't enough to compel a truce. Hitler would have needed the patience to wait for the British to elect a PM inclined to peace and probably a good amount of propaganda to convince the public that the Nazis were sincere in their claims that they didn't want war with Britain. Alternatively, Sea Lion might have convinced the British to take a truce even if they only could hold a small beachhead, but not going through it was actually one of Hitler's saner moments.