php code not running

As i continue with my first ubuntu server, following the lamp installation tutorial at https://www.digitalocean.com/community/tutorials/how-to-install-linux-apache-mysql-php-lamp-stack-on-ubuntu-20-04-quickstart-es i configured everything without much issue until i decided to create a different php script and upload it to the server. the code is supposed to show your ip (here is the script)

<?php

function getUserIpAddr(){
    if(!empty($_SERVER['HTTP_CLIENT_IP'])){
        //ip from share internet
        $ip = $_SERVER['HTTP_CLIENT_IP'];
    }elseif(!empty($_SERVER['HTTP_X_FORWARDED_FOR'])){
        //ip pass from proxy
        $ip = $_SERVER['HTTP_X_FORWARDED_FOR'];
    }else{
        $ip = $_SERVER['REMOTE_ADDR'];
    }
    return $ip;
}

echo 'User Real IP - '.getUserIpAddr();

?>

but when i connect to it through a web browser like ‘server ip/file.php’ all i get is the ‘User Real IP’ message without the actual interesting part wich is the ip, does this mean php isnt executing the code or what am i missing here