OK are you dialing a computer or are you connecting to a computer through a medium like telnet.
1) dialing a computer:-
When you set-up your pc to connect to a computer (or internet) you open ie (internet explorer) and click on tools:Options:Connections: Then u add a new connection, at that point you will see a box for your username a password.
2) Connecting to a computer:-
You are connected to the internet and you have an ip... So you open the program that you are going to use to connect to the other pc and enter the details (IP:PORT) and then you connect. If you only get a second to type the password or username that means the program on the other end thinks you are some sort of program to and can type really fast, so for example you are using telnet to connect to somesort of pc running a program that only allows you 2 secs to type the username, then u have to find the same program or make one for yourself.
Hope i helped.