The first part of the Interim Act relating to entry restrictions for foreign nationals out of concern for public health (external website) imply that foreigners who are not covered by the exceptions in the law or in the regulations of the law (external website) (content in link only in Norwegian) will be expelled upon entry into Norway. The law and regulations specify several exceptions for groups that can still travel to Norway.
For information on which entry rules apply to different groups see:
Due to the coronavirus outbreak, Norway will now normally reject applications for Schengen visas. Visas can only be granted in extraordinary situations. See New instructions on processing visa cases and the UDI's instructions on visas (external website) (link only in Norwegian) and residence permits during the corona visa outbreak. (external website)(link only in Norwegian)