How do i port forward?

I have seen countless videos showing me how to but it still wont work, i get told to open CMD and type ipconfig and i do that nothing happens whereas the people in the video get this huge *** list of ****. Then i get told to enter a certain number code into a web browser such as fire fox, and type a username and password of which i have no idea to find. If some one can tell me why and how to do this I will be very happy and will smile a lot :)