Supplements for brain fog

My husband has been experiencing brain fog for almost two months, his first time getting it was 2 years ago when he first got covid. It lasted for only two weeks and he was okay for a whole year until now.

He’s had MRIs done to rule out MS, he’s done acupuncture to help with the brain pressure but the effects don’t last long, he experiences inability to focus especially when driving. He was off work for two months due to the fatigue and brain fog.

I’ve been reading a lot about what others have taken and what’s worked for them, so far the biggest recommendation is NAC, glycine, and glutamine. Is there a specific way of taking them? Should he take one at a certain time and the others at different times or could he take them all in one go? If it makes a difference he does have high blood pressure and cholesterol.

Any help is greatly appreciated!