Solution
As an example of the NC-SI FPGA I/O in PCIe-8237R, NI recommends referring to the Vision RIO Configure Ethernet Action Command.vi.
This is because this example is configured for NC-SI I/O use on NI hardware (especially with NI Vision hardware such as PCIe-8237, CSV-145x and IC-317x).
You can find this example in the following path:
C:\Program Files (x86)\National Instruments\LabVIEW 2019\vi.lib\vision\driver\Vision RIO.llb.
If you cannot find vi on this path, you should make sure that you have installed the Vision Development Module on your PC.