Help on many wifi questions?

Your router will accept a connection from a modem from your internet service provider. the router will then enable you to connect multiple computers both wired and wirelessly to the router so that they can all share files, printers, and get online. you are basically setting up a small home network. but you have to have file and print sharing enabled and some resources shared like folders and printers before you can share files inside your network. basic configuration is all that's needed for internet connectivity. your router doentation will tell you how to get the internet up and running. Google file and print sharing for an explanation on that.