CBSE

According to the CBSE rules, if you fail in 3 out of 5 subjects in your class 12 exams, you will be considered as having failed in the board exams. In this case, you will need to appear for all 5 subjects in the upcoming CBSE compartment exams. However, if you have failed in only 2 subjects and want to apply for improvement in 1 subject, you can apply for both compartment and improvement exams. In this case, you will need to appear for the compartment exams for the subjects in which you have failed and also appear for the improvement exam for the subject you want to improve. It is important to note that the compartment exams are usually conducted within a few weeks after the declaration of the main board exam results, and the exact dates and procedures for applying for the compartment exams may vary depending on the CBSE rules and regulations. I recommend that you visit the official website of CBSE or contact your school/college authorities for more information on the compartment and improvement exams and their application procedures.

JIIT Noida offers admission to its B.Tech program through the JEE Main entrance exam as well as the 10+2 merit-based admission process. Based on your score of 95% in PCM in 2020 CBSE boards, you may be eligible for admission to JIIT Noida through the merit-based admission process.
However, admission to the CSE program is highly competitive, and the cutoff for admission through the merit-based process may vary each year depending on the number of applicants and their scores. It is recommended that you check the institute's admission criteria and cutoffs for the current academic year and apply accordingly.
Alternatively, you can consider other colleges that offer admission through the merit-based process and have a good reputation for their CSE program.