@rero You can find build instructions for DSF here: https://github.com/Duet3D/DuetSoftwareFramework/wiki/Build-Instructions
I just checked the build process and both DSF 3.5 and 3.6 build fine on my Windows and Linux setups. Unless you intend to make further changes in DSF, you don't need to build it, though. For the API bindings, it should suffice to pull in the dependencies from NuGet (DuetAPIClient). There are beta/rc packages available, too.