My experience so far:
Ep. 1
I have installed Centos 7, Centos 8 with Nginx and apache in different combinations for the last 24h. At first, It seems to work for my needs, but problems started to appear after SSL activation or adding a second domain.
My VPS is from https://contabo.com/?show=vps.
and DNS Zone Management
"If a domain name has not been registered by Contabo, it is required to perform a nameserver update at the current registrar of the domain.
The following nameservers need to be set for the domain: ns1.contabo.net ns2.contabo.net ns3.contabo.net" I did that.

For now, I installed Ubuntu 18.04 + aapanel 6.6.3 + Nginx + Php 7.2 + MySQL 5.6 + phpMyadmin 4.9.

I added 3 domains.
website1 - in backdropCMS
website2 - in Wordpress
website3 - in Drupal 7

https://prnt.sc/rsxb9m

I got SSL (Let's Encrypt Certified domain(s): website1.com、www.website1.com) for website1 and after that
I managed to redirect http://www.website1.com to https://www.website1.com (http to https)with this Config code

server
{
  listen 80;
  server_name www.website1.com website1.com;
  return 301 https://www.website1.com$request_uri;
}
server
{
  #listen 80;
  #server_name www.website1.com website1.com;
  #return 301 https://www.website1.com$request_uri;
	listen 443 ssl http2;
    server_name www.website1.com website1.com;
...........................

I hope that automatic renewal still works. I will try to renew the certificate in a few days.

I still get this warnings:

nginx: [warn] conflicting server name "www.website1.com" on 0.0.0.0:80, ignored
nginx: [warn] conflicting server name "website1.com" on 0.0.0.0:80, ignored
nginx: [warn] conflicting server name "www.website2.com" on 0.0.0.0:80, ignored
nginx: [warn] conflicting server name "website2.com" on 0.0.0.0:80, ignored

I had some problem with image file uploads on https://www.spare-wheel.com/suv-cars and I modified the Nginx Config:

https://pastebin.com/Wsu5Lj04
in particular

    # Fighting with ImageCache? This little gem is amazing.
    location ~ ^/sites/.*/files/styles/ {
    try_files $uri @rewrite;
    }

Updates will come...