How can I effectively transform my 10×17 room with magnifying windows into a square room or covered deck to prevent heat and water damage?

Hey there! So, I’ve got this room that’s 10×17, but the windows in it are causing some issues with heat and water damage. The room is currently sitting on a concrete foundation, and I’m thinking about either making it a regular square room or turning it into a covered deck or porch. Any advice on how to tackle this project?