Check if your laptop has a physical switch on the casing.
Try using FN key + F-Key to switch on.
Most laptops have an LED for wifi, is it on?
If you think it is on, check the system tray for a wifi icon, click it and Win8 will show a control bar from right-hand of screen, if you see wifi connections, click yours and enter secuirty key/passphrase to link to your router.
On the subject or router, you do have one providing wifi signal and not just a modem?
If still nothing, is driver installed, press windows flag key and pause together (sometimes need the windows flagg too) and then go in to device manager andd see if you have a wifi device under network adapters, any yellow exclamation marks means no driver or it has failed to...