Curved bridge

Ok, I’m going through the tutorial on UV mapping, and I think I understand the idea The Best Free 3D Modeling, Animation, and Rendering Software

Basically I need to assign a texture to each face of the object yes?

Now at this time I’m still doing very basic, I’m probably going to use one of Unreal’s default material/textures such as marble or maybe one of the brick ones. How do you tell what size those are so you can apply those properly. Can/should you import those into 3D max and then apply them there? Then I would import back into Unreal?

Thanks again,