Lost and confused in bridge world..can someone help?

I set up a wireless router for my friend. The signal was poor, so i purchased 2 additional routers (linksys Cisco) and set them in bridge mode because I thought they would act as access points and extended his converage. This worked, but when I connected to these routers I thought the SSID names would be the same as the main router, but instead it was just a random name given by the router (Cisco3457). When i connected to them, it asked me for the 8 digit code on the bottom of the router and then asked me to create a name! I did, but then it gave me a new security key! So now each floor has a different key and SSID. How do I fix this???? I want the SSID and the key they same as the main router. Please help.

Thank you,