If your site is currently configured to run on previous versions of PHP not supported anymore, you may get this warning on your WordPress dashboard.
In this article I will show you how to fix this issue through the CPanel configuration on your hosting server.
The warning section looks like the image below.
Login to your CPanel, go to the Software section. This section may be a little different depending on the CPanel version used in your site, but can help you as a reference. Click on the MultiPHP Manager option.
Your current PHP version will be displayed as in the image below. As you can notice, the current version in this example is PHP 5.6. The recommended version at the time I am writing this article is at least 7.2.
In the lower section of the same page you get a list of the active domains in your CPanel account and the PHP version for each one.
Check the domain that needs the PHP version changed and next select the version PHP 7.2 from the drop-down and click on Apply.
The version for the selected domain will be updated with the new configuration.
And if you go back to your dashboard, the PHP Update Required warning will be gone!
Hope this steps are helpful.