I've mentioned before that I'm thinking of bringing my webhosting in-house. As part of that, I installed Debian in a virtual machine here and started configuring it to be a web server.
Read about it here
The first task with any unfamiliar OS is to find where they put Apache. You might look in /etc/httpd, but that's not where it is on Debian. You could flail around looking everywhere, but a “find / -name httpd.conf” is how I found Debian's /etc/apache2 directory.
This had a structure I hadn't seen before, but it was pretty easy to figure out. I edited the 000-default file in “sites-enabled” to change DocumentRoot and ScriptAlias to where I wanted the web files to live and added Options Include so that I could use includes.