This should be a one-time setup. Once you've connected successfully to a WiFi network, the computer will remember it and automatically reconnect when it is in range.
The easiest way to reboot the computer is by pressing the laptop's power button. Alternatively, you can right-click on the blue area of the desktop to bring up the NoTouch menu, seen below.
Once the computer restarts, you should be able to press Ctrl Alt S to display system information and confirm that the computer is connected to WiFi.