To renew a Norwegian Student Visa, go to the Directorate of Immigration (UDI) website and log in with the same account you used when you first applied. This should be done three months before your residency permit expires.
You must also schedule an appointment with the local police department, where you must submit the necessary paperwork. Setting up an appointment could take a few weeks, which is why you should apply three months ahead of time.
You must not be behind on your studies in order to renew your Norway Study Visa.