The simplest way to collect the Client/Visitor IP address using PHP is the REMOTE_ADDR.
Pass the 'REMOTE_ADDR' in PHP $_SERVER variable. It will return the IP address of the visitor who is currently viewing the webpage.

Get the IP address of the website
<?php
echo 'User IP Address : '. $_SERVER['REMOTE_ADDR'];
?>
  
/*
I Hope it will help you.
Namaste
Stay Home Stay Safe
*/