@gittiharre , I haven't walked the route myself (enjoy!) however one quick comment about money in Norway - whilst you can still pay with cash, since Corona it appears that it is extremely rare to do so. Last year I was in Norway for a month, I took 200 NOK with me and had 170 still left at the end of the month. I needn't have even spent the 30 NOK that I did - they would have taken my card, it was just that my son had it and he was down the road at the time!
I almost exclusively used my debit card, the only exception was when I rented a car - for that they required a credit card.
I use a Wise card, because I can load whatever currency on it that I require, limit the funds on it for additional security, transfer additional funds almost instantly using the app, lock or unlock the card at will, use it to withdraw cash at an ATM, but also in place of a credit card online.
I am not for a moment suggesting you go with no cash but do limit it to perhaps 200.
Incidentally I was well and truly in the middle of nowhere on many occasions and the card was always accepted even just for an ice cream. It's now become the norm rather than the exception.
My son was there again at Easter this year for a week, he took the 170 with him and used exactly .... zero.... . He ended up giving it to his cousin to put into her bank account!