The MiFi has it's own phone number and connects to a cell tower for data transfer and it creates the WiFi signal. Using WiFi it's able to connect up to 15 devices (model dependent).
For W7 if the Icon is not visible then you bring up Network and Sharing Center and select the Verizon-xxx signal and you'll be prompted for the password. Also there will be a check box that is something like "Connect to this device automatically." You do something similar for all of your computers Linux, Apple, tablets, printers, etc. The procedure is basically the same as a router with WiFi.