How do you get smarter? You constantly engage your mind, get rid of things like videogames and television. Go to school, fill your free time with a personal pursuit of knowledge, try to get a job that requires attention, try to socialize as much as possible, exercise for 1 hr every 2 days at least.
People will probably knock the school part the most but at a good uni they can structure your learning so you don't go down some pointless rabbit hole, although those can be good too so long as you balance. Frequently study things in uni you are bad at, because they're much easier in a structured environment.
I know this because I came from a family of peckerwoods and I was scooping popcorn at 18 and reading on the side. I finally applied and shot through a private top uni with the highest scores in my class, didn't abuse adderall but occasionally used shrooms and drank. Exercise, socialization, personal reading, and the education system (so long as you go to a competitive school) can help transform you. 4 years ago I was on the chopping block to become a Petsmart employee, and I had flunked my way through a public inner-city high school.
