Use cPanel’s MultiPHP Manager to manage your domains’ PHP version. Being able to manage the PHP version that your domain uses means that you can continue to use older versions of PHP to run your websites whenever the system PHP version changes to a more advanced one. While we recommend that you update your PHP version as soon as you can, the settings in cPanel’s MultiPHP Manager interface provide the flexibility to implement those updates.
MultiPHP Manager for WHM – https://documentation.cpanel.net/display/78Docs/MultiPHP+Manager+for+cPanel
How to Install WordPress with cPanel – https://documentation.cpanel.net/display/CKB/How+to+Install+WordPress+With+cPanel