How do I treat brain fog?

Brain fog is usually caused by stress or exhaustion. Electronics are well known to mess with your brain chemistry too, so the first thing you do is spend less time on your phone or PC. Change of diet and exercise regimen will help as it will restore your metabolism and get your blood pumping properly. No alcohol, coffee or smoking during the afternoon, and try to just take a break, stop what you're doing and sit down in peace for a few minutes.