Within the first few weeks of your study a Teacher Coach will be assigned to you. The Teacher Coach will advise you with regards to the development of your professional skills (which includes assessment and training by the TU/e Skills Lab, see http://skillslabtue.nl/) and will help you in making the first choices for electives and in deciding which specialization best suits your interests.
At some point during your study your specialization will become clearer. This typically happens between the end of the second and fourth quarter. Your Teacher Coach will then help you in choosing supervisor from the group that best matches that specialization. The supervisor will then help you in selecting elective courses to prepare you for doing a master project in your area of interest and in selecting a trajectory for getting international experience (if needed). For more procedural aspects of your study such as obtaining approval of your study program and getting official permission to start your master project you should consult the academic advisor.