How to prepare for exams? Questions in the minds of students

Ninth to twelfth grade board exams are approaching across the country, A, AS and O level exams will be as per the schedule, while National board exams will be as per the new schedule, but students are worried about various questions.  Especially how to prepare for exams.
Students are very worried about the way the epidemic has affected the education system, how the exams will be, how they will prepare if there are exams, because online preparation can be very difficult, in this regard Many questions are circulating in the minds of Students.