Make Cloudflare cache Wordpress pages for 5 minutes

wordpress-cache-control.php

<?php 
if(!is_404()) {
  // Set caching headers (cache for 5 minutes)
  header('Cache-Control: max-age=300, must-revalidate');
  header('Expires: '.gmdate('D, d M Y H:i:s', strtotime('+5 minutes')).' GMT');
}