Once you and your family have arrived in Norway, it is important to have your residence permit effectuated within the first 7 days of your arrival if you are from outside the EU. If you are from within the EU, you will need to get registered as EU nationals living in Norway.
Proof of residence will then allow you and your family to apply for a Norwegian Personal Number, which is the key to services in Norway. You will need the Norwegian Personal Number to open a bank account, get access to a General Practitioner, order utility subscriptions, purchase insurance, etc.