Firstly create a new directory where the site will reside, normally:

/var/www/site-domain.com

Then change the ownership and permissions:

chown -R www-data:www-data site-domain.com
chmod -R 755 site-domain.com

Then duplicate the config file in /etc/apache2/sites-available

Typically a config file will look like this:

<VirtualHost *:80>
        # The ServerName directive sets the request scheme, hostname and port that
        # the server uses to identify itself. This is used when creating
        # redirection URLs. In the context of virtual hosts, the ServerName
        # specifies what hostname must appear in the request's Host: header to
        # match this virtual host. For the default virtual host (this file) this
        # value is not decisive as it is used as a last resort host regardless.
        # However, you must set it for any further virtual host explicitly.
        #ServerName www.example.com

        ServerName family-hub.online
        ServerAlias www.family-hub.online
        ServerAdmin [email protected]
        DocumentRoot /var/www/family-hub.online/

        # Available loglevels: trace8, ..., trace1, debug, info, notice, warn,
        # error, crit, alert, emerg.
        # It is also possible to configure the loglevel for particular
        # modules, e.g.
        #LogLevel info ssl:warn

        ErrorLog ${APACHE_LOG_DIR}/infinityloop.tech.error.log
        CustomLog ${APACHE_LOG_DIR}/infinityloop.tech.access.log combined

        <Directory "/var/www/family-hub.online">
                Options FollowSymLinks
                AllowOverride All
                RewriteEngine On
        </Directory>

        # For most configuration files from conf-available/, which are
        # enabled or disabled at a global level, it is possible to
        # include a line for only one particular virtual host. For example the
        # following line enables the CGI configuration for this host only
        # after it has been globally disabled with "a2disconf".
        #Include conf-available/serve-cgi-bin.conf
RewriteCond %{SERVER_NAME} =family-hub.online [OR]
RewriteCond %{SERVER_NAME} =www.family-hub.online
RewriteRule ^ https://%{SERVER_NAME}%{REQUEST_URI} [END,NE,R=permanent]
</VirtualHost>

Then symlink the file from /etc/apache2/sites-available to /etc/apache2/sites-enabled like so:

ln -s /etc/apache2/sites-available/family-hub.online.conf /etc/apache2/sites-enabled/family-hub.online.conf

Or use Apache's own enabler:

a2ensite family-hub.online.conf

To disable a site:

a2dissite family-hub.online.conf