Hi @supriya you will need to use the gaze direction as well as the gaze origin. Whilst the gaze origin is a point in world space where your eyes are looking from, the gaze direction is world space direction vector.
The gaze direction originates from the gaze origin in the direction whee you are looking which finally provides the final gaze location.
Unfortunately, your user case is non-trivial, but perhaps our included samples with Unity can help you get started.
Hopefully this helps you in your project.