~Had Hitler abided by the Molotov-Ribbentrop Pact and not launched Operation Barbarossa, Germany likely would have won the war.
But for sabotage in the war plants, Germany's jet fighters, the Me 262 and the JG7, would have been in full production and on line years earlier, while the British Meteor was still on the drawing board. As it was, the Me 262 flew almost a year ahead ahead of the Meteor and Lockheed didn't have the P-80 (the first US jet fighter) ready until Korea. With large scale production and deployment of the Me 262 as late as spring, 1944, Germany would have owned the skies. With bases at Brussels and Lille, the Swallow could have not only stopped allied bombing of Germany but could have easily escorted bombers to London.
The V-1 and V-2 rockets were light years ahead of allied technology (bear in mind that both the US and Soviet space programs relied significantly on the German scientists and technology developed at Peenemunde).
Had Heisenberg, Esau and company been given appropriate facilities and had the heavy water experiments not been sabotaged, Hitler would have had atomic bombs at Stalingrad. It is almost certain he would have had them at Normandy and it would have been a simple matter to deliver one on the invasion fleet by means of a conventional Ju 88 or He 177, either by free fall drop or possibly on a reconfigured Henschel He 293 or He294, but would have more probably been launched on a Rheinbote missile. The Rheinbote proved effective at Antwerp and, with a little more work, would have had sufficient range and accuracy to target most of England.
The waste of manpower, funds and resources on the camps and the extermination of captured civilians (many of whom could have and should have been assimilated) delayed the rocket program and delayed production of the German SAM missile program. The Hs 117 Schmetterling was on the verge of deployment at the end of the war and the radar guided Wasserfall was at the mass production stage in 1945. The Taifun was in mass production when Berlin fell.
Any one of the foregoing could have turned the tide of the war. All of them in combination would have brought England to her knees. Without England, the US supply line to Europe would have been untenable and the US would have sued for peace. Hitler would have granted satisfactory terms.
The allies were working on their own weapons, obviously. Rumor has it the the US still claims the distinction of being the only nation on earth to have used nuclear weapons. There were others. With a little research, I'm sure you can find what they were.