If you are planning on appearing for JEE Mains next year i.e. 2021,  the exam will be conducted on a reduced and revised syllabus. The MHRD has announced this and so is under the process of revisiting the syllabus to reduce it to match the reduced Academic year 2020-21 due to Corona Pandemic. This means you needn't buy many books right now because we do not know which topic will be omitted and which topic will be retained in the new syllabus for JEE Mains. So what we would suggest you is to stick to NCERT books atleast until NTA or MHRD come up with the new syllabus. That way you will not be investing in a lot of books and then told that the topics have reduced. Sticking to NCERT means you will not go out of syllabus and not invest money and time in topics that might be out of syllabus. We can help you with few tips as to how to concentrate for studying. This is a tested method called PATS.

Picking the Best Environment for you to study: This is important because you should feel secure and comfortable but not too comfortable where you might fall asleep.

Always reducing the visual distractions: Make sure you have nothing within your vicinity to distract you. Like keep your phone a side. Or sit away from the TV, Windows where you can see people.

Try to Eliminate Noise around you: If you are someone who can concentrate with music, make sure it is light music and nothing to distract you. It should increase your ability to concentrate and not distract you. If there is any noise that might distract you, use ear plugs or a fan. Trust me, if am being distracted by noise, I switch on the fan and it works.

Self talk to control Internal Distractions: When you are noticing that the mind is drifting aside, stop what you are upto and keep a check mark on a piece of paper along with the time. Keep a track of these check marks and the timings. Talk to yourself that you understand you are being distracted but you also have to study. If it keeps bothering you, write down what is it that is bothering you and promise yourself that you will come back and look into that. Now that has been parked in the notebook, get back to studying.