How to generate UV map as 2D from the 3D glb Model and draw image on UV map apply on same meshes on 3D model in Three.js

[IntruderMan]

Hi I am trying to generate 2D UV map from the 3D model in Three.js dynamically and after than i have to draw image on 2D UV map image will be apply as texture on 3D model.
I tried so many ways to do it like us png UV map by generated blender and us in three.js project but issue is getting when resize the 3D model by length, width and height so its not working on png uv as same coordinates.

I also use 3D model in unfold mode as UV of the same and us febric for the image drawing so here getting issue with height, when change it so its reflect on thickness which are increasing ( width and length working well when change size)
How so solve this issue can anyone pl help that how can fix it.