This is an error with a popular CMS called MotoCMS.
In order to fix this, we’ll first needto make sure we have a working php configuration setup on the server.
Once that is done, you might have to access the admin panel to update CMS in order for it to work properly. You access admin panel by adding /admin to the installation page. Say: http://your_domain.com/admin/
You should then be able to access both the website and the admin panel without any issues.
You can refer this official article for installation guide: MotoCMS Official