Dishant, The previous year papers and sample papers of CBSE CLASS 12 board examination are necessary to analyse and understand the exam patterns and the important areas to work upon in order to perform well in the exams. These question papers give an opportunity to test our preparation and make some changes in our strategy, if needed. Through the sample papers and by answering and analysing them, students can know about exam pattern, marking scheme and the style of asking the question. CBSE has released the sample papers already and you can download it on the official website or from the link which I am going to share with you. Here I am providing the link where you can download all the sample question papers and hope that they would help you in your preparation

https://school.careers360.com/articles/cbse-class-12-sample-papers