Absolutely, but acquiring a weapon legally is a process involving the police and requires a sensible intent (like hunting, sports or defense against polar bears) and an approved safe storage. While there are a lot of weapons in Norway, it's very heavily regulated.
With that said, the terror in Norway was performed with a firearm which was obtained legally with approval from the police, so the system is far from perfect.
2019 – Cyclone Idai makes landfall near Beira, Mozambique, causing devastating floods and over 1,000 deaths.
2021 – Burmese security forces kill at least 65 civilians in the Hlaingthaya massacre.