For installing laravel passport make sure you add this line to config/app.php in the providers array (package service providers section):
Laravel\Passport\PassportServiceProvider::class,
Then install the package and migrate the database
composer require laravel/passport
php artisan migrate
php artisan passport:install
Clearing out the cache is generally helpful first step when commands are not working, especially when you update anything in the config folder on .env files.
php artisan config:clear
php artisan config:cache
Config clear removes the configuration cache file. Config cache creates a new configuration cache file with the current settings. Config cache enables faster load times for your apps!
