Hie,
Assuming you are talking about the board exams. I would suggest you to either go for self-study or seek guidance from an expert if your school teacher has not completed the syllabus. There is ample time for you to prepare for the exams. You can refer the previous year question papers or the recent exam pattern to know the weightage of these chapters and thus could divide your time accordingly.
Hope this helps you!
All the best
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