ditch your phone, take short timed 10 minute breaks every hour, coffee, plan out exactly when you’re gonna lock in for a few hours before and schedule it in so there’s no conflicts, start with the smallest task and progressively take on bigger tasks, full night of sleep the night before, (amphetamines, specifically adderall), train your brain by spending time reading every night (start with 20 minutes and then increase), also there are certain neutropic peptides that can benefit i haven’t researched but the ones ik of are semax and selanc, another really helpful method ive started using is recording myself in time lapse (preferably with a window with a sky view in the background) to motivate myself to get a cool video of me studying really hard for hours while the sun sets