C:/Users/YourUserName/AppData/Roaming/Microsoft Flight Simulator/SimObjects/Airplanes/FNX320.
There will be 2 files, and 2 files ONLY in the FNX320 folder. State.cfg, and Cameras.cfg. If there are more, then you are in the wrong directory- likely in the actual sim install location where the Official and Community folders are. There is a similar folder structure there (SimObjects/Airplanes). That is NOT where you want to be.
If you’ve downloaded a custom cameras.cfg file, for the Fenix, follow the above directory tree, and drop the file in there to replace the existing cameras.cfg file.
How to access the views? It is the( EDIT) Left-Alt key and the 1 through 0 numbers at the TOP of your keyboard, and NOT the number pad on the right, if your keyboard has them.
Can they be assigned to the number pad? Yes but you will need to remap your keyboard via the sims control options.
EDITED: Left-Alt Key, Not Right- Alt.