Problem With Grid And Camera

Parlour1.blend (1.06 MB)

I am having trouble in this scene getting the camera in the right perspective and getting the grid to be straight. The camera seems to be in portrait mode and I do not know how to get it in landscape mode or increase the horizontal view). I deleted the camera and added a new one, but it still appears in the same format. If you look at the scene, it looks like the whole scene is slanted even though there is no rotation on X and Y applied. When I use the MMB to pivot the grid, the grid stays slanted at an angle and none of the rotation points (active element, cursor, origins, etc…) fix the problem. I don’t know how to fix it.

You change the X and Y resolution of the rendered image in the Render dimension settings

Your objects are not level and the camera is below the scene so not sure what you are trying to do.
Unless you have a bad builder, rooms are not tilted like your scene. Change its X and Y rotation back to zero