It's a quite good wave spot to begin. Waves aren't too big but you can surf them, they generally come from the right (when you look to the sea). Shore break isn't too strong but can be a little bit irritating for the beginner. Bridge to the north.
On this side of France, weather is a little bit fresh but during summer you won't need a wetsuit. During the coldest month (from November to February), the water isn't more than 5°C.
Usually, wind isn't too strong like 15-20 knots. You can kitesurf about ten days a month. No particular best seasons. You can get on any beach around Rivedoux for different wind directions.
There is a big bridge from France and you will have to pay (10/20$ depending on the season). You can also come with bus from the rail station or the airport of La Rochelle. You will find lots of parking space just next to the beach.