I'm trying to find out. I'm trying to find out on how to connect my other computer wireless to my

Question

I'm trying to find out on how to connect my other computer wireless to my 2wire. My other(desk top) has a linksys card in it. It was already setup for Linksys Broadband Router, wireless-G 2.4GHz 54Mbps. I can see that it list on the site survey screen. Operation sys i'm using is XP. On my daughter Lap top(Dell Inspiron 1721) it ask for a security key or passphrase. Thank you.