Make textures look like holes in Blender

[Andamanians (AndamaniansTheDev)]

Hey there developers!

I need help with blender do anyone know how to make textures look like holes and yes can use PBR textures

Example

That is the textures not hole!

source : Nambu Type 99 Machine Gun - Download Free 3D model by Alexander Kirby (@alexanderkirby) [82365df] - Sketchfab