Now, to run multiple domains on one web server, you need to create a so-called virtual host. When a browser calls your web server, the browser also transmits the exact domain name and based on this information, the web server then displays a directory set for this domain.
To provide this functionality, you must create a virtual host for the domain in the Apache configuration.
Under Debian GNU/Linux, these are managed in individual text files under /etc/apache2/sites-available/. Here you can see a VHost declaration for the named domain, "example.org", this is representative for the domain you want to create and you have to replace it with your domain:
Options FollowSymLinks MultiViews
allow from all
CustomLog /var/log/apache2/access.example.org.log combined
Save this file under the name "example.org". After that you can activate it with the following command:
# a2ensite example.org
...and finally restart the web server with the following command:
# service restart apache2