To connect to the wifi in the college building you need to find the eduroam option on the list of networks in your network and internet settings on your device, on a laptop you just need to click the wifi icon on the bottom right of the screen.
To connect to eduroam you use your full student email address (make sure to include the x) as your username, so for example x12345678@student.ncirl.ie. The password to connect will be your college password which you use to log onto Moodle and your college email.
If this doesn't work you could try right clicking on eduroam and "Forget" the network as your machine may have cached an old password before trying again, failing this you may have to reset your password (see FAQ below).
If you still can't connect to the eduroam network you may have to submit a request with the NCI Support Hub.