Since Kernel32 is not a COM library, you cannot use COM interop to call its functions. However, you can use Platform Invoke.

For example, to reference the MoveFile function from Kernel32:

Code:
public class wrapper
{
   [DllImport("Kernel32.dll")]
   public static extern int MoveFile(string moveFrom, string moveTo);
};

// and then...
wrapper.MoveFile(@"C:\test.txt", @"C:\test_moved.txt");
HTH.