The standard model I have seen for viewing a scene is a camera where the camera is set and the elements are placed in front of it. The window is what is seen through the lens of a camera and when the the window is resized the the scene as viewed through the lens stays the same but the elements in the scene get bigger or smaller depending on how the window is resized.
What I would like to do and need some guidance on is how to keep the elements the same size regardless of how the window is resized. Kind of like looking through a real window, when I make the window larger I see more of the scene. The elements I am viewing through the window do not change size I just see more of them.
Does anyone understand what I mean and can you help? I feel I am missing some crucial concept and cannot grasp what it might be.