Glad to hear you are willing to learn!

I would say Apache would be a good start. You can add Varnish later, once you get your sites configured properly. But honestly, with DigitalOcean’s SSD drives, I think you will find your sites load in split-seconds, even without Varnish.

For starters:

I take it from your original post that you are able to SSH in to your server, and can use Filezilla to access your server via SFTP. You will be using both for various things.

Most likely, the folders you will want to work with for your website files will be in /var/www
The folders where you can configure your websites are in /etc/apache2/sites-available

Can you access those?

UPDATE Following the suggestion in the first reply I started from scratch again as the Virtualmin panel seemed to using a lot of memory and adding more complexity.
I discovered “easy engine” and installed that on a fresh droplet with Ubuntu 14.04 and Nginx . I can access the server with Filezilla and have successfully installed one Wordpress site using easy engine.
My next problem is to migrate another live Wordpress site with three subdomains. I have “backup buddy” installed on the main site so maybe I can use that to help with the migration.
My biggest concern (apart from screwing up the migration) is the downtime while DNS propagates.
At this moment I am trying to work out if the Wordpress contact forms will work “out of the box” or if I have to configure a mail server. Respect to you guys that master this technology, I am finding it challenging!
Thanks for taking a look at my question it is much appreciated.

the WordPress contact forms use phpmail, which you can install with:

sudo apt-get install sendmail

configure sendmail

sudo sendmailconfig

it will ask a few questions, just accept the defaults.

then restart nginx (I think with):

sudo service nginx restart

As far as propagation down time: theoretically, if you have an exact clone of a website on the new server, the public will not notice any down-time…

Unless....your site is an e-commerce, or takes input of some kind. In this case, you would need to disable all of those things until the site is fully propagated. Otherwise you will have purchases, or comments or whatever in your old database, and not on your new one.

But if the site is just information, then no one will notice because the domain will be pointing to either the new or the old site, which should be exact clones.

But that is all theoretical and in a perfect world. The truth is, stuff happens…often there are configurations you miss on the new website, so when it propagates some errors pop up and you end up scrambling to fix things.

Because of this, I usually start the switch late Friday night, and tell my clients things will be running normally by Monday morning. This gives me the weekend to track how the switch is going and fix problems as they pop up.

Thanks for the info about Sendmail, now about to install. I guess it can be set up for more that one site on a server so I will do some research.
I used “easy engine” to install Wordpress Multisite with subdomains thinking that would simplify things, not sure if it was a smart move but I am learning a lot!
Regarding installing live sites I have discovered the Duplicator plugin and think that may help me migrate sites onto subdomains, doing some research on that now.
If not I will dig deep and go for it manually, thanks for your suggestion about the 14.04 set up, on my test site page load times are FAST compared to my old shared host.

Multisites can be useful in certain use-case scenarios, but comes with its own set of issues.

One problem I ran into with Multisites: I hosted several people’s websites, and it worked great, but certain people over the years needed to move to their own servers for various reasons.

Moving a single site OUT of a Multisite install is not as easy or straightforward as when each site has its own install.

PROS:
only one site to update WordPress, monitor, etc.
keeps your admin-time focused on a single install

CONS:
if a site needs to move, is not as easy
some plugins do not work on Multisites
running backups for each person’s website is not as easy..since you need to seperate the content for each site.
Can be a bear to configure and work properly.

..probably some other things I am not thinking of.

Hmmm you got me thinking!
I guessed there would be issues when looking at the Multisite dashboard.
Maybe its better if I try to figure out a way to install Wordpress on normal Subdomains and bin the Multisite option as I have live sites with specific themes and plugins to migrate.

My intention is:
mysite.com
Subdomain: bodybuilding.mysite.com
Subdomain: slimming.mysite.com
Subdomain: tba.mysite.com

Thank you so much for your input

I do not want to completely discourage you from running Multisites. It does have its benefits. But you should be aware of the possible issues as well before you dive in.

My experience is that all of the issues arose when dealing with other people’s websites that I had on my multisite install. Looking back, I would not run someone else’s site on a multisite installation, but keep them on their own WordPress install.

Also: no need to completely bin the Multisite. You can use it to run just one of your sites, and have it on hand if you need to quickly create a sub-domain site, for example, testing and building a theme.

I keep one multi-site installation going for just such a thing. Is handy because I can create a new site in minutes....then delete it just as easily.

Since starting this thread I have made mistakes and had to start again but now have a much better understanding of how Wordpress and file systems work.
For sure at my age it has been challenging to get my head around the technology but hey, I now have a working server!
At this point I feel happy working from the command line and do not miss cpanel. For sure there will be other problems for me to solve but its nice to know there are such helpful and knowledgeable people here to lend a hand.
Thankyou.