Opening RAW file formats in gimp 2.10

[PurpleArachnid]

I am trying to use gimp to edit NEF (nikon RAW) files, but it gives me this message:   

There is no RAW loader installed to open 'Raw Nikon' files.

GIMP currently supports these RAW loaders:
- darktable (http://www.darktable.org/), at least 1.7
- RawTherapee (http://rawtherapee.com/), at least 5.2

I attempted to add RawTherapee, but must be doing something incorrectly because i am still unable to open the files in Gimp.

Could anyone tell me which of the loaders they recommend, and how to install it so it will properly work with gimp? 

Thank you!!