You should never put on your high beams - it makes it much worse.
You should use low beams when driving in fog. It is more difficult to see driving with high beams in fog.
You should never use high beams when you are driving in fog because they shine up and ahead which will be reflected straight back into your eyes by the fog. Low beams (which aim downwards) and front fog lights (which are lower) are far better suited.
Use the low beams if your car is not equipped with fog lights. It's never recommended to use high-beams in fog, as it makes it about 4x harder to see, and makes the fog look denser.
No, you should not.
low beam
NO
fog light and/or low beam
No, you should not.
low lights
When driving in fog you should always use your low beams. Using your rear fog light when visibility is less than 100 meters is also a really good idea.
Yes
go slower. leave your lights on. turn on your fog lights(if you have them) and do not turn on your bright lights!(in heavy fog) it will make it difficult to see for you and other drivers.