It is required by law that everyone who lives in Germany - no matter for how long - needs to have a health insurance. Therefore it is an obligation to have health insurance coverage for the whole period of your stay in Germany. In case of a health emergency or an injury, you are insured and do not have to pay for any medical examinations (which could be very expensive in Germany).
With Fintiba Plus, you can easily cover all your health insurance needs in one solution: