Automatically assign hundred of textures to .obj file

Good evening, I'm experiencing an issue while trying to apply automatically a texture to an .obj file with hundreds of meshes (I cannot do it one by one as they are too many). Firstly I load the .obj file, the .mtl file and all the textures into the Assets, then I drag and drop the .obj file into the Hierarchy. The problem is that Unity assigns a default material instead of using my textures. Can someone please explain me the correct steps to follow in order to achieve this purpose? Thank you!