I have used the following repository
https://github.com/elic-dev/laravel-site-protection

To install:
composer require elic-dev/laravel-site-protection

Open [app/Http/Kernel.php]

Add this variable in Middleware array (protected $middleware = [];)
\ElicDev\SiteProtection\Http\Middleware\SiteProtection::class,

Add passwords on .env file
SITE_PROTECTION_PASSWORDS=password1,password2

That’s it!