I'm studying +2 in TN board. Total marks for me is out of 600 marks and each subject carries 100 marks I have six subjects.

Dear Aravindhan, 70% of seats in Sastra University for B.Tech are filled by JEE Mains scores. The rest 30% are filled by marks scored in your 10+2. You should have secured a minimum aggregate of 60% in Mathematics, Physics and Chemistry/Biotechnology/Biology/Computer Science in aggregate in a single sitting. So 60% is the minimum aggregate that you should score to be eligible for B.Tech in Sastra University if you want to take admission based on your 10+2 marks. Which means any score lesser than 360, you wont be considered. Now 360 being the cut off there is no caste reservation for admissions into this college. However 40% of the total seats will be allotted to candidates who hold domicile of Tamilnadu. The competition is also bssed on the stream you choose because each stream has different no. of seats. So if in any particular stream there are 100 seats, 70 seats are gone through JEE, you have to compete with candidates vouching for admission in 30 seats quota. Now 360 being the cut off, the competition is going to be tight. And to with stand this you should score nothing less than 500-550 to get a seat in your desired stream.

Hiii

In SASTRA University, Btech seats are filled through two streams.
Stream 1 - 25% weithage is given to JEE Mains score while 75% weightage is given to marks scored in Board exams to prepare the ran list and selection list. 70% of total seats are filled through this stream. And you must score a minimum of 60% in class 12th exam and a decent rank in JEE Mains.
Stream 2 - 100% weightage is given to board marks. So you need to score around 90% in your boards to get selected. Only the remaining 30% of total seats are filled through this stream so the competition is very high. Minimum marks required for being eligible to this option is 60% marks in class 12th. But yes the higher the marks, more is the chance of getting selected so keep a high target.

In case you opted for stream one but did not appear in JEE Mains, the 25% weightage will still be given to mains and for you it wold be written as 0 marks in mains. So choose your stream wisely.

Incase you need any more help or have any more doubt feel free to ask.
Refer to following link for more details - https://engineering.careers360.com/articles/sastra-btech-admission

Thanks!!