Warning: require(app/index.php): Failed to open stream: No such file or directory in /var/www/public_html/index.php on line 41

Fatal error: Uncaught Error: Failed opening required 'app/index.php' (include_path='.:/usr/share/php') in /var/www/public_html/index.php:41 Stack trace: #0 {main} thrown in /var/www/public_html/index.php on line 41