Brain fog and fatigue

I have daily brain fog which makes it pretty hard to focus, on top of always being tired. I don’t remember a day where I woke up rested and could think clearly. I’m at the point where it really impacts my life and work quality at my job. I don’t want to be a “bad employee” but it’s hard for me to even get out of the bed in the morning, and then I drag throughout my day.

What are tips / lifestyle management to make this better?