You have 14 days after arriving in Switzerland to register with your cantonal migration office. You’ll need to apply for a residence permit at your cantonal migration office if you have a long-stay category D visa. You’ll need to present your ID, Swiss visa information, and proof of Swiss address during the first 90 days of your stay.
A successful application will result in a B residence permit, which is only valid for a year but can be renewed. It could take a few weeks for this to come, and you won’t be able to leave the nation during that time.