I really wanna learn Norwegian!
My grandmother is Norwegian, and I really wanna learn it so I can speak to my grandmother! Or is there any other alternative to learn Norwegian?
What do you mean by "Or is there any other alternative to learn Norwegian"? Beside Duolingo? People have been learning Norwegian since long before Duolingo came around, so of course there are. That being said, you won't find near as many materials on Norwegian as the more widely spoken languages.
One day there will be a Norwegian course though, so if you really want to learn Norwegian via Duolingo, then you could just focus on Portuguese for now until there is a Norwegian course.