These are end-to-end samples which means that most of them have both client and server code. The server code could be written in .NET, Node, Ruby, etc.
The code samples (except as noted) are maintained in the breeze.js.samples repository on github where it is maintained continuously between releases of BreezeJS itself.
Perhaps the easiest way to try it is to download the latest version from github as a zip.
For older versions you can pick a a commit (e.g., a tagged commit) and then click the “Download Zip” button.
Once you have the zip on your machine
Unblock it (a Windows security button on the zip properties sheet).
Now locate the sample of interest.
The breeze.js.samples library is divided by server stack into different sub-directories:
net - Microsoft.NET server samples with Visual Studio solution and project files
Many of the .NET samples have Visual Studio solution files and you can often just launch-build-and-run in Visual Studio.
Some require a little preparation first, e.g., downloading supporting libraries and installing sample databases.
Look for a sample-specific “readme” that describes how to install and run.
Your OS may interrupt the build flow with security questions, especially if you neglected to “unblock” the zip. Just play along, saying “yes … go ahead and do that”, every time it presents a scary message and asks if you really want to proceed.