How to apply points texture to custom 3D model?

Hello,
Im working on a project where i need to display custom 3D models (FBX or GLTF) but with points material. jusl like here : Dala
My main question is, how to replace my Meshs with custom 3D models and keep the points Material.

my work so far : https://codepen.io/Imsenji/pen/QWOBMWN

Thank you !