The Viewport Shading menu is in the header of the 3D View window. It lets you choose between the different methods of shading the objects displayed. While you may want the Texture display when you need to show an object's appearance, quite often, the Solid and Wireframe views will be best for modeling:
Use the Tab key to get into Edit Mode in the 3D View, if you are not already. If you are unsure, look at the button on the header near the left-hand side of the 3D View window. It will say either Object Mode or Edit Mode.
Move the cursor to the Viewport Shading menu, as seen in the next image. It's the same one that you used to change the mode to the Textured mode, when you were playing with the lighting.
Now, select Wireframe mode. What is different about the 3D View?