PHP is the software that powers most web sites, including all Wordpress sites. It's always best to run the latest version if your site is fully compatible. This will ensure your site is the most secure possible, and the fastest. It's easy to change the PHP version using cPanel using the following steps. Note, after upgrading to a new version of PHP it is important to check your site to ensure everything is working properly. The latest version of Wordpress is always 100% compatible with the latest version of PHP, but some plugin and theme developers tend to lag behind, so thoroughly testing your site after upgrading is imperative. If problems are found then simply downgrade to an earlier version of PHP until all of your plugins and themes have released updates.
1. Log into your cPanel account.
2. In the Software section, click on the MultiPHP Manager Icon.

3. Scroll down to the bottom of the page, select your domain from the left side of the screen, and see an option PHP Version with a drop-down menu on the right side. Please select the appropriate PHP version from it and click the Apply button.

After clicking the Apply button it will take a few seconds for the upgrade/downgrade to complete.