ft2build.h is located here:
C:\\Program Files\\GnuWin32\\include
Initially, I made the same mistake as here:
Fatal
Have you installed freetype properly? If you have, there should be a file named ft2build.h somewhere under the installation directory, and the directory where that file is found is the one that you should specify with -I. The string "GnuWin32" does not appear anywhere in the output of your build command, so it looks like you have not placed that directory in the correct include list.