Exactly the same question was asked by a traveller yesterday. Please read the answers in the link below. 

https://community.eurail.com/routes-destinations-42/last-minute-train-from-rotterdam-to-paris-8841

You are an absolute Saint!!! Thank you so much for this. We really don't mind hopping from train to train - so those options they have are perfect Thank you @AnnaB 

@Kym Mitchell Did you already plan out your trip to France? There’s a comprehensive itinerary for you  https://www.ricksteves.com/europe/france/itinerary depending on how many days you’ll be staying there or are you interested in getting to know more specifically in Paris https://gowithguide.com/united-kingdom/paris you might consider these resources. You might find it helpful.