To "Shell" a solid obect, you select the object, then remove any faces/surfaces that are to be removed, then assign a thickness. In other words, if you select a BOX to Shell, and remove only one face, you'll end up with a hollow box with one open side. If you remove two opposite sides from the box, then you'll end up with a square tube with open ends.
You have to switch to 3D Basics or 3D Modeling workspaces to have access to the Solid Editing panel(s)
![Autodesk Design & Make Report](https://forums.autodesk.com/t5/image/serverpage/image-id/1350519iCB55845EBFC43016/image-size/large?v=v2&px=999" "Autodesk Design & Make Report")
