I wrote a simple test code for mail in PHP on my remote server RHEL 8. But when I trigger it doesn't sent mails to me. What is the issue can anyone tell me? Is there any configuration I need to do in php.ini file?

CODE

    <?PHP
       // the message
       $msg = "First line of text\nSecond line of text";

       // use wordwrap() if lines are longer than 70 characters
       $msg = wordwrap($msg,70);

       // send email
       mail("sudipta.s@gmail.com","My subject",$msg);

       ?>

I'm using PHP 7.2, RHEL 8, apache 2.4. Any clue to solve it?