I just installed the latest version of Laravel and tried to run the following command from my Git Bash:
php artisan migrate:make create_users_table --table=users
In your root directory you have artisan.php file which is internally triggering Illuminate\Console\Application::start($app);
So follow that path and see what is happening. Do you have any output when you run php artisan ? That error is usually shown when artisan is not in your path (current directory).