travelling to Normandy from Paris on a 1 day tour

I recommend Overlord tours. They do tours that leave from Paris and Bayeux.

Christine,

That's a challenging tour to do from Paris, due to the travel times back and forth. There are tours such as Paris City Vision that offer one and two day tours from Paris, but many of those focus on the American sites. It could be challenging to find a tour from Paris that only visits Canadian sites.

While you could take the train from Paris to Bayeux, you'd need transportation to get to the specific sites you're interested in. The best option would be to spend one night in Bayeux, take a one day tour with Overlord Tour or one of the others, and then return to Paris after the tour ends. It would be a long day, but it's certainly possible.

There are direct trains from Paris St. Lazare to Bayeux with a travel time of ~2H:15M each way. The earliest departure appears to be 07:05, arriving 09:19. There's a late departure back to Paris at 20:06, arriving 22:26. You'd also have to allow time to get from your hotel in Paris to Gare St. Lazare.

Could you clarify what you're referring to as the "Canadian War Memorial"?