Creating a Fog Sheet

I want to create a layer of fog just above the ground. I found this: Fog Sheet and Light Beams | Unreal Engine Documentation
It seems to be what I want, but it’s not exactly thorough in its instruction. I’m new to UE. I’m not sure about how to create a Material Instance Dynamic and put it in the blueprint (is it the material blueprint, or another blueprint?) I can’t seem to find any video tutorials on it either.

In the construction script or off

of begin play you can create a Dynamic Material Instance and create a variable from the return and then set your parameter values from the variable. Like this: