First, log in to Plesk as ‘useradmin‘, click on the ‘Domains‘ icon, and then select the domain you wish to install PHP for.
Next, click on ‘Web Hosting Settings‘.
Scroll down, and place a check mark next to ‘PHP Support‘, and click ‘OK‘ at the bottom of the page.
Once receiving the confirmation that the command completed, you should now be able to view PHP pages under the domain with no issue.
If you need any assistance with this process, or encounter any issues, please don’t hesitate to contact our Technical Support Department.