Hello Ankit Singh,
Model paper of physics of 2020 of BSEB can be downloaded by going to the link given below and by seeing the model paper ,you can understand how the question are going to come in the exam and by knowing that ,you are going to prepare well for the exam.
https://school.careers360.com/download/sample-papers/bihar-board-12th-physics-model-paper-2020
Hope this helps you..
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