If you (for whatever reason) like to use the npm version bundled with node, add the direct path to your global Angualr CLI version. After this your path variable should look like this:
If you are using Git Bash and also you are sure that you have done all steps that are listed above, still getting an error like this, run following command:
alias ng="C:/Users/<your-username>/AppData/Roaming/npm/node_modules/@angular/cli/bin/ng"