Muhsin Abdul Majeed

Dear Kajal,
First of all, you should never distress yourself thinking about your inefficiency and lack of concentration during studies. No one can get a cent per cent concentration while studying. It instead becomes distressful when you force yourself to learn. Instead, you should calm your mind and get the best of your mood to think clearly and better understand the concepts.
A well-disciplined study plan and timetable has to be made. Set goals everyday attainable by you, rather than keeping impossible goals which only further demotivate you and will end up devastated. It is always essential to make the concepts clearer to you rather than rushing through topics.
I would recommend you to spend daily at least 15 mins doing yoga which undoubtedly will improve your concentration to its peaks. It would help if you also spent time introspecting where you are slacking and sorting out problems that distract you.
Class 11th and 12th provide the necessary foundation for the courses you wish to master in the future. It is essential to give your best effort to embrace the concepts and better understand the course every time you go through it.