Whoever set up your router should know what those are - you need to use the network key, not the passphrase.  On some router, you can log on to the router's configuration page and see the network key in the wireless security section.  On other brands of routers, all you will see is the dots, in which case you won't be able to determine the key.  If the person who set up the router does not the key and the router is one of those brands that does not reveal the key, then you will have to reset the router to its default settings which disables the security completely and resets the username and password to log on to the router to their default settings.   Then you will have to set up the router again, this time writing down the security key and keeping it in a safe place so you won't forget it the next time you have to set this up.

 

Steve

Most Routers have a button on the Router (usually recessed so accidental pushes don't occur) that resets it back to factory defaults, which include no password. Use this to reset and then set your password o something you know.