Bielefeld University is unable to provide the services of study assistants. Whether and how far a study assistant seems necessary is something that students and potential students need to appraise for themselves. Special counselling services outside the university are available to clarify this very individual issue.
You can obtain initial information here (in German):
Office for students with a disability or chronic illness [RSB] of the Student Union [AStA] at Bielefeld University
Information and advice centre for students with a disability or chronic illness: Competence centre Disability - Study - Career in NRW [kombabb]
The Studying with Disability Information and Advice Centre [IBS] of the German National Association for Student Affairs [DSW]
In principle, all issues regarding, for example, study assistants or the use of aids exclusively for studying (integration support for disabled persons) are the responsibility of the regional welfare authorities. In eastern Westphalia, this is the Landschaftsverband Westfalen-Lippe.