ash3T glad that helped 🙂 metabullet.com is Linux guru you can ask any small question. mark sir is very friendly person he is always super excited to share the tips/tricks/knowledge you start a discussion there.
There is video about server hardening from linode youtube channel you should watch it.
You may feel like it's hard to manage a server but it's very simple.
Don't tell your IP to anyone (create own name servers or you can use Cloud Flare)
Change default ports
Keep everything up-to-date
That is all I think, Use a SSH key instead of password.
Install fail2ban at server level (this in my list I have to do for my server)