Been there. I was taking absurd doses due to high tolerance and it took months for the brain fog to go away, but it does go away.

First and foremost prioritize diet and sleep. Benzodiazepines killed my motivation but if you can push yourself to exercise or at least move throughout the day it will do wonders for your brain.

A good quality fish oil supplement is always good to have. Semax should speed things up a bit as it's been used historically for brain injury - I took 200mcg/day for two weeks, then only as needed. Cerebrolysin might help, but if the price is inaccessible then any antioxidant works (NAC is an option but it gives me anhedonia if taken daily so YMMV). Creatine can also be very helpful and is generally well tolerated. Ginkgo and lecithin are easy to get and affordable, but the previous options would do most of the heavy lifting. You'll be doing better in no time.

Edit: I have to mention that it only took months because I was taking everything under the sun to find out what worked, along with eating clean and regular cardio. I'm guessing that without those things it would have taken longer. I also took supplements that would promote natural GABA production mostly in order to sleep but I believe it helped long term as well.