Been a few years but there are plenty out there...for example:
https://www.pariscityvision.com/en/n...anding-beaches
A lot of our colleagues make the mistake (IMHO) of taking the train on their own which is rather grueling, especially at the end of the day coming back to Paris on your own. You will Metro to the Gare du Nord train station, then have to train out there. At the end of the day you will have covered a lot of ground in Normandy and the return leg back would suck. Spend a little more and find the tours that pick you up and drop you off at the end of the day in Paris at your hotel via coach. Well worth the minimal extra cost and you'll be glad you did.
Another piece of advice: Don't wait for the perfect trip or time to do your "bucket list" of things you want to do and see. Show up at brief and mention it to your colleagues and if there's no interest, don't let that deter you! GO solo if you have to...For example, 1 other pilot joined me for Normandy but when we climbed into the van we were immediately greeted by several Brits and Canadians. By the end of the day we all felt like old friends.
My Normandy day trip was one of the highlights of my career. It's a once in a lifetime trip not to be missed. It will make you very proud to be an American (if you're not already) and you will be awed and moved standing amongst the rows of crosses in the cemetery. There are still grateful French citizens who spend their days outside the museum in Caen handing flowers to americans and thanking them for liberating them. Been there and seen it...ought to be required as part of your TOE.
Good luck and enjoy!