Students have different possibilities to find accommodation in Germany:
Student dormitories offer furnished rooms and flats, usually in close proximity to the universities. However, places in student residences are often very limited, so you should be quick to apply and might have to wait for a few semesters.
Current offers by Studierendenwerk Bielefeld can be found here.
Students often live in a shared flat (German: “Wohngemeinschaft” or “WG” for short). As rent and utilities are shared, costs are lower than in a flat of your own. Shared flats are a great opportunity to get in touch with German students.
Of course, students can also look for a flat of their own. It is the option that is most quiet and private, but also most expensive.
Further information and a list of student residences, accommodation portals and other services can be found on the Studierendenwerk’s website.