I have heard great things about Spring Valleys B12 drops (I found it at Walmart for $7). I only just started and so I can’t speak to it myself but I know a lot of people have seen benefits. One dropper under your tongue for 30 seconds. I also try to get as much natural light as possible and I have found the app Endel helps me a lot with focus. It uses different sounds/frequencies/etc. I just use the free version. Hope this helps!

I've heard Moringa helps, I think there is powder and there are seeds. I'd do some research on it if I were you, YouTube has videos on it