Creating a three dimensional object is an important skill for any artist to be able to accomplish. In order to make an object on a flat surface three dimensional and create atmospheric perspective, an artist sometimes has to exaggerate what is already there. For this project, it would be the lighting. If looking at the stripes on the chair in person, they may look like the same shade of gray, but to achieve a 3-D look, the lines closer to the viewer must be darker and the ones father away must be lighter.
I went back and fixed my drawing after our critique. I added more shadows to the right side and I made the atmospheric perspective less extreme.