Here’s the proper way to host multiple websites (domains) on single host with a single IP address. Technically, you can have multiple Apache configuration files that you can enable within Apache, but you can easily simplify and combine them into a single Apache configuration file. You can separate each domain by creating multiple virtualhost sections as shown in the example below.
DocumentRoot "/www/example1"
ServerName www.example.com
# Other directives here
DocumentRoot "/www/example2"
ServerName www.example.org
# Other directives here
If you’re interested, read up on Apache’s website about virtual hosts.