Once you have received your certificate of matriculation, you can get access to your so-called UniAccount. The account will have already been set up for you, so you only need to activate it.
Instructions how to activate your account can be found here.
The UniAccount is the key element of most digital services at the University of Kassel: Only by means of the UniAccount can you use your own university e-mail account and register for courses and exams. It also enables you to connect your electronic devices to the University's wireless network, or use one of the numerous computer work desks in the so-called "computer pools" of the IT Service Centre (ITS). You can find further information on your UniAccount and other digital services on the ITS website.