In Genesis, Noah placed a door in the side of the Ark.
Genesis 6:16 describes the Ark’s arrangement and says that Noah was to set its door in the side. The same verse mentions a lower, second, and third deck, presenting the vessel as a multi-level structure rather than a simple open raft.
The window is a separate feature in the account. Genesis says Noah made a window, or opening, near the top of the Ark, while the entrance was placed in the side. Because both features appear in the construction instructions, they are sometimes conflated.
The text does not call the entrance a gate or specify a modern hinged design. “A door” is the direct feature named in most English translations of Genesis 6:16.