Key path "file:///var/www/html/appointment_system/storage/oauth-public.key" does not exist or is not readable code example

Example: Key path "file:///home/user/projectname/storage/oauth-public.key" does not exist or is not readable

#Install passport
composer require laravel/passport

#Register the service provider in config/app.php
Laravel\Passport\PassportServiceProvider::class,

#Run the migrations
php artisan migrate

#Generate key
php artisan passport:install