These guides assume the simple case where everything is installed on the same server (if there are exceptions, it will be specified in the guides).
You should start by installing the base server, and then install the components you need. If you do not have a server handy, or it's just to test, the simplest is to get a virtual machine with Linode. If you are a software developer, you'll be interested in the source code.
If you prefer to hire someone to install for you, please see Support options.