How to change the laravel config file reference env file to database settings

How to change the laravel config file reference env to database settings.

Example: laravel\config\captcha.php

return [
    'secret' => env('CAPTCHA_SECRET', 'default_secret'),
    'sitekey' => env('CAPTCHA_SITEKEY', 'default_sitekey')
];

Instead of env function i want to use eloquent model Settings::where('key','CAPTCHA_SECRET')->first()->value()

via Chebli Mohamed