The shelf in the first picture is made of red oak plywood. You can choose the wood type, color and design as you like for your project. In case if you need more help understanding this project, you can refer the source link below. It discusses various items used, steps and tips and personal experience of the author who personally built a Zigzag shelf.
You can transfer a graphic on any wood piece of your choice, including a frame, top of a table, etc. The surface should be clean and big enough for the graphic paper. I am also sharing a video tutorial here that explains in detail the process of transferring any graphic to a wooden surface using a freezer paper. Just gather the items you need and follow this video to carve your favorite designs on your favorite wood items.