Warning: require(./routes.php): Failed to open stream: No such file or directory in /var/www/html/index.php on line 16

Fatal error: Uncaught Error: Failed opening required './routes.php' (include_path='.:/usr/share/pear:/usr/share/php') in /var/www/html/index.php:16 Stack trace: #0 {main} thrown in /var/www/html/index.php on line 16