If you would like to use the French Civilization, you want to be on the more aggressive side. They have a powerful Cavalry early on and you can overpower your opponents even before the Feudal Age. Below is one of the rush build orders you can do using the French Royal Knights.
Double French Royal Knight Build Order
Put 8 Villagers to sheep and build a house. Put 3 Villagers to Gold and 3 to Wood. Get 1 Villager from wood and make it build the School of Cavalry. Put 4 new villagers to deers and get 4 villagers from the sheep and put it to deers as well to delay the need for Farms.
Research Survival Techniques and get 1 more builder Villager to help build the Cavalry. Put 2 Villagers to Wood and once the 2 builders are done, send them to Gold. Get 1 Villager from the wood and build a stable. Afterward, send the 4 villagers to sheep and 5 more villagers to Gold. Research the Chivalry and send 6 Villagers to Berries. Once you get your Royal Knights out, you can go on the offensive with your opponent.