Hi @devora-holder, thanks for getting in touch. You will be pleased to know we have created a tutorial for the Stream Engine using C# .NET which you can find @
We also cover the required syntax to obtain the eye position and head position @ https://developer.tobii.com/consumer-eye-trackers/stream-engine/getting-started/#tobii_streamsh
Please go through these links and let us know how you get on! Best Wishes