An ARK is and ARK

Noah's ark was not boat shaped. It was the world's first water SHIP vessel. Like the Ark of the Covenant, it was shaped like a cabinet.
Not saying there hadn't been other BOATS. After all the Earth was always covered with waters .. oceans, seas, lakes, rivers.

GENESIS 6
15 Make the boat 450 feet long, 75 feet wide, and 45 feet high. 16 Leave an 18-inch opening below the roof all the way around the boat. Put the door on the side, and build three decks inside the boat—lower, middle, and upper.