Entartet is an installation. It is experienced like a visit to a gallery. You are free to spend as much or as little time inside the installation as you want. Entartet runs continiuously, so there is no fixed beginning or end. Within the installation you can move around freely to take in the different elements, shaping your own experience.
Depending on the venue, you might be given a certain time-slot to start your experience. If this is the case, you don't have to arrive at the beginning of this time-slot, just arrive at any time during it.