1. remove everything around you that is not relevant to your learning/working session.

for example:
your phone? probably not needed, shut it off and put it in another room,
extra tabs? probably not needed close them and only have tabs that are relevant,
social media and texting? ignore the pulse to read or write a text.

why is this crucial?
it takes your brain minimum of 10-20 minutes of uninterrupted work to reach a state of high productivity and absorption, often called a "flow state.", one context switch(checking your notification, texting someone, watching a reel, etc) can ruin your flow.

2. you wanna stay hydrated and take strategic breaks like stretching, cleaning your room or doing some chose, the point is that you don't wanna be so stimulated that getting back to what you were doing feels hard. the point is that you want getting back to your work easy not hard.

3. don't overeat, cuz that would make you feel lazy since your body would be too busy digesting the food.