If Nazi Germany surrendered in 1943, it would have drastically changed the course of World War II and the post-war world. Here are some possible outcomes:
The war in Europe would have ended earlier: If Germany had surrendered in 1943, the war in Europe would have ended much earlier, possibly saving millions of lives. The Allies could have turned their attention to the Pacific theater and ended the war against Japan sooner.
The Soviet Union would have gained more territory: The Soviet Union suffered heavy losses in the war and probably would have demanded significant territorial concessions from Germany as part of the peace treaty. If Germany surrendered in 1943, the Soviet Union would gain more territory than with the actual peace treaty. The Cold War Didn't Happen: The division of Germany and the emergence of the Soviet Union and the United States as superpowers after World War II set the stage for the Cold War. If Germany had surrendered earlier and the Soviet Union had gained more territory, the geopolitical landscape might have been different, perhaps preventing the Cold War from happening.
The Holocaust may not have been fully revealed: the liberation of the concentration camps by the Allied forces in 1945 played an important role in revealing the full extent of the Holocaust. If Germany surrendered in 1943, it is possible that the full extent of the atrocities committed by the Nazi regime may not have been fully revealed to the world.
The reconstruction of Europe after the war could have been different: in the post-war period, the Marshall Plan, which provided help for the reconstruction of Europe after the war, would not have ended the war. In addition, the division of Germany and the creation of new political structures in Europe could have looked different if the war had ended earlier and the Soviet Union had gained more territory.
All in all, it is impossible to know exactly what would have happened if Nazi Germany had surrendered in 1943, but it is clear that it would have drastically changed the course of history.