If you don’t know much about France, one thing that is really important to understand when planning a trip is that the French take their vacation very seriously. Most of the French (particularly Parisians) take either the entire month of July or August off. That means stuff shuts down, restaurants close, and if you happen to visit in August you’ll hear more English than French being spoken.
We knew of this phenomenon and chose to travel at the very end of August with most of our trip taking place in early September. We would still catch warm summer weather, but not have to bother with the August vacation crowds or lack of locals.