Blending face and makeup texture into a single one

How to blend multiple texture like face and makeup on the go through code. I am using react three fiber.

This is more of a React three fiber question. You can check their Material and MeshStandardMaterial documentation pages.
If you encounter an issue, I’d suggest posting in their forum or reaching out to their support

I wants to know how you guys are doing on your backend api, just wants to know the logic

Here you can find more info of what was used: CanvasRenderingContext2D: globalCompositeOperation property - Web APIs | MDN