Now I want to place some 3d model (example earrings/ necklace/ spects/ Hat/ Beard ) on these dots detected by the above project. I am unable to find any tutorial/ leads. Any help?
So a number of folk from our community have managed to overlay things like face masks etc so they may be best placed to answer this as this is more about a co-ordinate system transformation if I remember correctly.
Essentially you have 2 co-ordinate systems - one is the real world (camera view) and the other is three.js virtual world - they are 2 different systems.
You will need to make your own custom mapping to take data from one and use in the other.
This guy from the community has successfully done things in this space and probably has the most well implemented examples he may be able to share with you (or check his github as it may already be there):