Change PHP version on Plesk
Plesk has the accompanying PHP versions installed:
Follow these steps for changing the Plesk php version to switch between these versions:
1. Log in to Plesk.
2. In the left sidebar, click Websites & Domains.
3. Click Hosting Settings:
4. Choose the version of PHP you wish to use under Web Scripting and Statistics from the PHP support (PHP version) list box:
5. Click OK. The new setting is immediately implemented.