Do I need to apply for a leave of absence at the Freie Universität?
Erasmus+ students are not obliged to apply for a leave of absence. Nevertheless, it is often used, because the semester of leave is counted as a university semester, but not as a subject semester and therefore no study time is "lost". You can apply for the leave of absence at the student administration office, and you can obtain a corresponding proof of your study abroad from the Erasmus team.
You can find more information about the semester of leave here.