A plane is a thing that you can use to cut layers of wood, for example if your shelves are slightly too wide. A file is a large sort of strip of metal with a very rough surface, and you file off a few millimeters of wood. Rags are bits of cloth, maybe old t-shirts or old clothes or whatever that you don't use anymore,. You might need a dust pan and brush, as well as a multi-tool - which is like a Swiss Army knife in one tool.