You may become a tax resident of Norway if you spend more than 270 days in Norway during any 36-month period. All whole or partial calendar days in Norway count, and the days do not need to be consecutive. Tax residency generally applies from 1 January of the year in which your total stay exceeds 270 days.
https://www.skatteetaten.no/en/person/taxes/get-the-taxes-right/abroad/tax-when-you-move-to-norway/