Getting running error while testing codelgniter

I am testing CodeIgniter 4, but I am getting this error:

Fatal error: Default value for parameters omegle.2yu.co with a class type hint can only be NULL in C:\xampp\htdocs\CodeIgniter4-develop\system\Config\DotEnv.php on line 121

What am I missing?

CodeIgniter4 requires PHP 7.4+
See https://codeigniter.com/user_guide/intro...ments.html

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