I suggest experimenting with the HVACTemplates directly in EnergyPlus.
When these are included in an input data file, they are expanded by a pre-processor.
You can then view the expanded input data file which will effectively show you how to put together the associated system
Standard HVAC systems are available as HVAC Templates (VAV, FCU, PTAC, etc)
Also the university course available on the internet is pretty out of date by now and will lead to errors in syntax.
The capabilities of energyplus have expanded since that was created (thanks Linda et al), so while the general concepts will be useful, the course will be missing quite a bit of functionality