A warship that participated in the Normandy landing campaign should be a supply ship. Now it is on display as a museum with the submarine in front of it.
There is no toilet on board, so please go to the public toilet before boarding. Boarding a ship requires climbing stairs, and then climbing down a ladder to get into the ship. There are lots of interesting videos and gift shops. The video lasts about 40 minutes. You can also look on the deck.