It’s not actually all that hard to do. The following guide can help you achieve this.

https://www.howtoforge.com/tutorial/how-to-install-joomla-on-debian-9/

You will need to be somewhat comfortable working on the command line. As well the guide uses PHP7.0, you may be able to use a newer version. To see what you have available in your repository you can use the following command:

sudo apt update && sudo apt-cache search php | grep php7

Hello, @LexusSocial

You will first need to setup the LAMP (Linux, Apache, MariaDB, PHP) or LEMP (Linux, Nginx, MariaDB, PHP) stack on your Debian 9 droplet. In order to do that you can follow our tutorials for LAMP/LEMP stack on Debian 9

For LEMP:

https://www.digitalocean.com/community/tutorials/how-to-install-linux-nginx-mysql-php-lemp-stack-on-debian-9

For LAMP:

https://www.digitalocean.com/community/tutorials/how-to-install-linux-apache-mariadb-php-lamp-stack-debian9

Once this is done you can then continue with the actual Joomla installation. To install Joomla, you will need to download the latest version of the Joomla. You can download it from the Git repository with the following command:

wget https://downloads.joomla.org/cms/joomla3/3-9-17/Joomla_3-9-17-Stable-Full_Package.tar.gz?format=gz

You can then navigate to the /var/www/html folder or to the root directory of your domain name (you should’ve already created a virtual host for your domain name) and simply extract the downloaded Joomla core files.

If you’ve downloaded Joomla in another directory make sure to move/copy the file to your domain’s directory and then simply execute this command:

sudo tar -xvzf Joomla_3-9-17-Stable-Full_Package.tar.gz -C /var/www/html/yourdomain.com

You should’ve already set the correct ownership and permissions of the domain’s root directory but if now you can do that using these commnads:

sudo chown -R www-data:www-data /var/www/html/yourdomain.com
sudo chmod -R 750 /var/www/html/yourdomain.com

You can double check your virtual host file and it should look like this:

nano /etc/apache2/sites-available/yourdomain.com

<VirtualHost *:80>
ServerAdmin admin@yourdomain.com
DirectoryIndex index.php
DocumentRoot /var/www/html/yourdomain.com
ServerName 192.168.0.145
ServerAlias www.yourdomain.com
<Directory /var/www/html/yourdomain.com>
Options FollowSymLinks
AllowOverride All
Order allow,deny
allow from all
</Directory>
ErrorLog /var/log/apache2/yourdomain.com-error_log
CustomLog /var/log/apache2/yourdomain.com_log common
</VirtualHost>

You can restart apache:

sudo systemctl restart apache2

If you access your domain name (or the IP address if you’re not using domain name) you should see the Joomla Installation Page.

Hope this helps!

Let me know how it goes.

Regards,
Alex