Advanced users might have a need to use install.php in some scenarios, such as setting up a multisite Drupal instance. If you require a copy of install.php, you can download current or previous releases of Drupal from drupal.org. Once you have the release you want, you can extract it on your local machine and upload only the install.php file to your cPanel account. This file will normally be placed in public_html, but may be deeper in the directory structure if you have installed Drupal in a subdirectory.