Everyone person based on an employment contract (in the case of a commission contract sickness insurance is voluntary) has the right to receive sick leave. This leave is issued by a doctor electronically (e-ZLA) and then goes to the employer’s PUE profile. So you don’t have to worry about delivering them to your employer. However, this does not release you from the obligation to inform about your absence!
You acquire the right of sick pay after 30 days of continuous sickness insurance (in the case of voluntary insurance, it is 90 days) until then you are in a waiting period. The amount of sick pay is 80 or 100% depending on the reason for your inability to work. It is based on the average monthly salary paid in the 12 months preceding the month in which you became unfit for work.
If you are employed through a temporary work agency, remember that you must provide its data to the doctor who issues you sick leave.