Usually, you will connect each image texture to a corresponding input socket in a node. For instance, you will find that we have a roughness input socket and a texture called roughness. But we don't have anything that looks like ambient occlusion. How do we connect the texture?
In this case, we have to blend the ambient occlusion with the color texture.
Using the Shift + A keys or the Add menu, go to the Color group and pick a MixRGB node. Change the node mode to Multiply and connect the output of both image textures' color and ambient occlusion maps.
And finally, you can connect the output from the MixRGB to the Base Color of your Principled BSDF:
Figure 5.11: Mixing two image textures
