Question on Port Fowarding

I'm trying to port foward my router, but when I type in default gateway into my url a notification prompts up saying "Authentication Required" A user name and password are being requested by http://192.***.*.*. The site says: "Netgear". I have to type a username and password, but I'm not sure what username and password to use. I've tried the one I use to log into my account and my WiFi user name and password as well with no success. I have administration rights set on my account. I'm like third person to make an account on this computer. Do I have to use the user name and password of the first person to make an account on this computer?

Look through your router's manual or search for login information on the web.

Try "admin" as username and "password" as password if not try "1234" as the password.

Yeah, that's what I did and finally worked. I tried typing in admin and password before, but it didn't work. I must of mispelled password and checked it off.