In order to obtain the individual or classroom license of Matlab, you need to first register on the MathWorks website, using your @agh.edu.pl or @student.agh.edu.pl e-mail address. If the website will prompt you to select your country, choose "Select United States".
The individual license should be already added to your account. If that did not happen, or if you would also like to use the classroom license, click "+ Link an additional license" and enter the appropriate license number: