Open PhpMyAdmin and Create a Database:

Example:

database name: yourusername_nextcloud

Select the Database from the left panel

Create Username - yourusername - and Grant All Privileges for the username on the database.

db username: yourusername

on: localhost

db Password: $Pwd#4646116 (Something that meets complexity requirements)

SSH to login to the server and obtain a command line prompt. Make a directory names downloads.

sudo mkdir /downloads/

Change directory to the downloads directory:

cd /downloads/ 

Download the nextcloud-19.0.0.zip file using the option to change the target filename to nextcloud.zip in the /downloads/ directory.

 
sudo wget -O nextcloud.zip https://download.nextcloud.com/server/releases/nextcloud-19.0.0.zip

Example Extract Folder to the path of the root directory of the website:

/var/www/exampledomain/public_html/examledomain_com/nextcloud/

Install Unzip utility

sudo apt install unzip 

Unzip the nextcloud.zip to the root, which will place the files in the nextcloud sub-directory. So the target subdirectory should terminate at /exampledomain_com/ because /nextcloud/ will be the directory where the nextcloud files will be extracted per the structure within the Zip file.

sudo unzip nextcloud.zip -d /var/www/exampledomain/public_html/exampledomain_com/

Make the Apache web-user the owner of the nextcloud directory so that the Apache server has read and write access to the website root and all subdirectories.

sudo chown www-data:www-data /var/www/exampledomain/public_html/exampledomain_com/nextcloud/ -R