You don't necessarily need the Function (fn) key to turn on wireless...
You need ...
A Wireless device
A driver for it (you will have lost this when installing a new O/S)
Control Panel NETWORK settings
You need to establish a network link to your router.
This will not be possible without the device driver for the wireless card....
Control Panel Network & Internet is your best approach. You can connect & disconnect with a click of the mouse button.
Good luck...
Peccavi, February 2013
