Ubuntu Server high processor and memory usage.

Hi,

A friend of mine is having issues with his Ubuntu server. He is wondering about the high processor usage. I don't know about the memory though. Plus, he's using Plesk. When I checked his Control Panel, I don't see any installations of Wordpress or any other applications. So, the entire LAMP stack might have been installed manually via SSH. I will be attaching some of the screenshots.

I have no idea how to optimize it.

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Another thing, I am planning to implement Cloudflare. But, I don't know if I have to manually change all of the settings of the domains or I will just install the Cloudflare application in Plesk.

Thanks.