brain fog is ruining my life

I've had brain fog for 3ish years now and its taken such a toll on me. I used to get straight A's and I had a pretty decent memory so studying has never been much of a problem for me until I got this brain fog.

It just feels like I can never fully concentrate on anything and I feel like I'm constantly zoning out even when I try not to. It's even worse in whenever I'm in class because I just can't seem to grasp whatever my professor is taking about even if I had learned it before. I also can't seem to rememeber anything I study at all and I always feel like I'm falling behind :(

I've been to multiple doctors but it feels like they're not even trying to help me figure out what's wrong with me. I've been on anti-anxiety medication for a few months but I honestly just feel worse than before. I eat healthy and I try to go to bed at reasonable times every night, but I haven't been exercising because I've been busy with uni. Other than that there haven't been any changes in my life.

Any advice? I just want to feel normal again lol