Hi Rohan,

This is a problem that every student faces in their school days the solution to this problem is very easy that you need to complete your sleep cycle timely and take light nutritious meals in short breaks of every 3-4 hours. Avoid heavy meals, junk foods, foods rich in fats and overeating as they will make you feel lethargic and sleepy also try to include a workout session of 1hr everyday, decrease your screen time and take short quick breaks between long hours of study.

Hope this helps you.