I searched online and I couldn't find updated information on how to open Nikon NEF file in paint.net. When I search in this forum, I find few topics, but those links in those are broken.
I install Nikon | Download center | NEF Codec (nikonimglib.com) and still I see no difference. My OS is Windows 11 64 bit.
Windows was able to open the NEF in photos application without above plugin.