So Im new to this Reddit but I always that the Question why did France occupey Germany after WW2? France was occupied by Germany for about 4 years and it really was the USA, Britain and Soviet Union that defeated Germany. Countries like the Netherlands, Norway or Poland could also just occupy Germany if France occupied Germany.
You seem to be greatly underestimating the contribution of France to Germany's final defeat. Without going into the roles of the French Resistance and the Free French, the French First Army was a major Allied formation in the invasion of Germany, with some 320,000 French and colonial troops. This made the French the third-largest Western Allied formation in 1945, after Britain and the United States.
Max Hastings, Armageddon: The Battle for Germany, 1944-1945