I am wondering how to use NUnit correctly. First, I created a separate test project that uses my main project as reference. But in that case, I am not able to test private m
You can make your methods protected internal, and then using assembly: InternalsVisibleTo("NAMESPACE") to your testing namespace.
assembly: InternalsVisibleTo("NAMESPACE")
Hence, NO! You cannot access private methods, but this is a work-around.