When you had set up your wireless router, you would have given a pass phrase or what you may know as a password. That's the network security key, which you need to configure/hook up your wireless adaptor with the wireless router.
please use this link to generate your network key
https://www.grc.com/passwords.htm
Do not use the key shown on the link....Refresh the screen a few times (at least once), copy and paste it on the wireless router and on your wireless adaptor