If you have made customizations to your PHP settings within Site Manager, you will want to utilize a local custom php.ini file in your new cPanel account. Please see the related KB article on this process How To Change Custom Local PHP Settings.
Your Site Manager PHP configuration file is located in /etc/php.ini. If you are upgrading from PHP 5.3 or lower to the PHP 7.2 on the cPanel shared servers, you will need to ensure that all your PHP code is made compatible with the new version of PHP. For more information, please contact our technical support team.