Is it possible to create new points on the AR face ?

Hi, I am a unity programmer who is new to using AR. I would like to be able to create points (like those already present on the AR face) and place them on the face. I have tried a technique using x,y,z coordinates but the problem is that since I am creating new points in relation to the AR face points, all I have to do is move my head and my points are no longer in the same place (so they are not fixed on my face like the basic points are).

How can I make sure that my points can be fixed on the face and that they follow the movement of the head?

Is it possible to create new points on the AR face ?
 
 
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