How to find my own security key?

[Suz_13]

Try to set up a new computer in my son's room. We were wireless network before. Someone else was able to set up correctly for us but I didn't see how it was done. When I try to set up his computer so he can access the internet from his room, it asked me for a security key. Where is that key?

 

[nhasian]

How to find or change your wireless security key