Hello Iris,
Remember to take breaks during studying. And even have no-study days to recharge, get rid of stress, and get a good sleep.
Remember to have a good intake of Vitamins B, C and magnesium.
You may also try to just cut it into smaller tasks and focus on that.
And u may try these fields:
https://forum.enlightenedstates.com/t/stop-procrastinating-supercharge-your-willpower/34676
https://forum.enlightenedstates.com/t/stress-and-anxiety-by-manhattan/74555
https://forum.enlightenedstates.com/t/the-plasma-light-and-infrasound-bioactive-beach/9903