Originally Posted by isleofthanet
I am with Plusnet for my desktop pc and 02 for my phone so that doesnt make any difference then?
Of course it makes a difference but, unfortunately, you omitted to tell us that in your OP.
The password you need is the WIFI password. (sometimes called wireless access or words to that effect) It will be on a label on the back of your router. The network that you need to choose will also be on that label and is called SSID or network name.
The O2 bit for your phone makes no difference to connecting to your WIFI it is the Plusnet Router wireless password and the router SSID or network name that you need and these will be printed on your router.