Registration in Amsterdam
It is a general requirement that you are registered with your local municipality during your time in the Netherlands. This will provide you with a BSN number which is required for opening a bank account, registering with a doctor, and working in Amsterdam.
Outside of the start appointments you may register at the Town Hall (Gemeentehuis) or one of the City offices. It can take a number of weeks to receive the BSN if you are registering in Amsterdam (a few days in Diemen).