Hiii

Yes ofcourse, You can start to study from now only. Make a schedule based on  your daily routine. Include all your activities in your timetable. Give 4-5 hours to study and during these 4-5 hours, study with full concentration and focus and be very honest and dedicated towards your studies.
Give equal time to all subjects and focus on areas which you are weak in.
Do not stress youself and take rest to work efficiently.
Kee your mind and body relaxed and active.
Focus on NCERT first and once you are done with NCERT then refer to other reference books to improve your performance.

And remember hardwork done with dedication never fails. Stay focused and honest.

Thanks!