"nootropics" that are marketed as such are all useless, ESPECIALLY piracetam and all of its shitty indian knockoffs (aniracetam, randombullshittam, etc.). take this unsubstantiated, unregulated powder for around a year before you can become "smarter"? hahaha i don't think so. you know what actually makes you smarter? thinking for yourself & not being a lazy cunt.
almost everything discussed on nootropics forums is just well-marketed alternative medicine.
the studies compiled by examine.com have shown piracetam, rhodiola rosea, bacopa, st john's wort, and many other herbal remedies to have "slight" correlations to subjective bullshit like "focus" & negligible, or even potentially harmful, correlations to reaction time and your physical health (liver damage is a common trait).
you should also know that rhodiola rosea & bacopa got major attention in the USA because of Dr. Oz. unless you live in a hole, this should raise some red flags. he's a sham artist that works in conjunction with these shady indian fuckers to target housewives & their insecurities about their intelligence & health.
in the end, even major hubs of nootropics discussion like /r/nootropics recommend caffeine and l-theanine over everything else (but you don't even need the latter if you don't overdose on caffeine).
just get a healthy amount of sleep & manage your caffeine intake to ~100 mg a day; you'll be as focused as you'll ever be. honestly, you shouldn't even take caffeine daily, as building a tolerance causes irritability & aggression when you're going through withdrawal (even if the withdrawal is relatively short and harmless).
i've met too many idiots who take adderall recreationally for me to recommend it. if you legitimately have ADHD, it does wonders, but it reduces acuity for otherwise mentally healthy people. also, amphetamines are notorious for causing long-term liver damage & dependency.
if you aren't diagnosed with anything wrong, you need to come to realization that nothing beats honest-to-god work ethic. just man the fuck up and stop making excuses for yourself if you aren't getting shit done. if it's school that you're worrying about, then you need to realize that failure is a natural process of learning. don't take criticism maliciously, surround yourself with intellectually healthy & accepting people, and your confidence will improve a lot quicker than if you stay cooped up and take fake drugs while berating yourself.