I have bad ADHD. I basically can't code or do anything mentally tedious without pills. No matter how much sugar, caffeine etc I take, my brain doesn't want to. I have gone months without, exercised properly and tried low sugar diets etc, tried everything, nothing worked. I made some tiny gains, as do everyone, how you treat yourself still matters for handicapped people. But then I got those pills, and now I can happily code many hours per day, my handicap is gone, it changed my whole life, without it I would never have gotten a good software job etc.

Note, those pills aren't really "stimulants", they help you focus they don't make you stressed out or high like sugar or caffeine does, they just help you get into the "zone". Maybe they do get you high to some degree and that is why some use them as a drug, but they don't really have that effect in the dosages you take them for ADHD, the feeling I'd call it is "a kid on Christmas eve", that makes it hard to sleep since you want to do so many things, not like caffeine at all. The dosage which made a night and day difference for me felt like nothing to a normal person.

So at least give it a try. Worst case it doesn't help much, best case it changes your life.