Security is not an absolute thing, it is a continuous process. Adding an SSL certificate and Website Security to your website is an important thing to do but in addition to that, your server must be configured in a way to reduce the damage that happens when your website is hacked.
Implementing Functional Isolation
A logical separation of websites should be implemented into separate hosting accounts having their own access. In the case of applications, you should avoid installing and testing multiple applications in one directory.
If you own a server, simply create multiple hosting packages separately for important websites so if in case anytime your website is hacked, the malware should stay limited to that particular hosting account of your website and other sites remain unaffected. This is called functional isolation. It is important because malware files are coded in a way to get automatically copied to various directories on your hosting account.
How to do logical separation of websites?
Linux is a multiuser operation system and your server (both VPS & Dedicated Server) offers you the feature to create multiple hosting accounts with separate cPanel logins. You can decide the limitation for each hosting account on your server.
Simply start by logging into your Sangkrit.net account then open the WHM of your server. On the WHM dashboard, you can create separate cPanel hostings from the Packages -> Add a Package option.
Most people understand the need of protecting their websites and keeping regular backups only after they face data loss after some malware or hacking of their website. Avoid being that person.