BoOZE is right for fog on the inside.
If you’ve got fog on the outside (or rain), you can buy small wiper blades that fit over your gloved fore-finger. I have one on my “Winter Gloves” full time. For the rain, you’ll also want to periodically put Rain-X on the outside of your visor.
Rain-X is an absolute *must* for wet weather riding in my opinion (if you want to be able to see that is).