Based on your previous question we understand that this is about JEE Mains. No you needn't attend all the sessions. Only the best of 4 will be considered and if you appear only for 1 session, only that score will be considered and your rank will be calculated. JEE Mains will be conducted 4 times a year from now starting from February to May. The first session will be held from February 23rd to 26th and the registration process has begun at https://testservices.nic.in/ExamSys21/Registration/Instruction.aspx . You can also download the Information Brochure at: https://jeemain.nta.nic.in/webinfo2021/File/GetFile?FileId=1&LangId=P The examination will be held in English, Hindi, Bengali, Gujarati, Assamese, Kannada, Marathi, Punjabi, Tamil, Telugu, Urdu, Odia and Malayalam. There is no negative marking for few set of questions. This means,  there will be no negative marking in the 15 alternative questions. The candidates have to attempt 75 questions out of 90  or 25 out of questions 30 in each section of Chemistry, Physics and Mathematics. To qualify for JEE Mains, there is no minimum aggregate criteria. But if you want to join NITs, IIITs or CFTIs then you should score a minimum aggregate of 75% only in your 12th. 11th marks aren't considered. And then to appear for JEE Advanced which is the gateway for admission to IITs, you will need to fulfill the 75% aggregate condition. Now it is 75% for General Category and 65% for Reserved Categories. So how much you score in 12th is what matters to secure your eligibility for NITs, IIITs, CFTIs and JEE Advanced.Candidates who have passed Class 12 or equivalent exam in 2019, 2020 or those who will appear in 2021 are eligible for JEE Main 2021.

Hello,

NTA has announced that JEE Main 2021 now will have 4 sessions - February, March, April and May respectively. The application form will be released soon in December.

Candidates can apply for more than one JEE Main exam in the December application form itself but candidates have to pay the JEE fees for the number of sessions they opt for.

Good Luck