SASTRA (Deemed to be University)

Hello Ashish,
Yes, you can get admission at Sastra University. You have a good score in JEE Main and board exams, which will eventually lead you to a good course.

Yes, there are chances for you to get a rank below 500. You have a good score so you may get a good rank.
Today's evening, probably at 9 pm you can check your ranks at www.sastra.edu

Yes, there are good chances for you to get a core branch in SASTRA University like ECE, EEE, mechanical, etc. as you have a good score.
On June 10th, they will be releasing the rank list in the evening at www.sastra.edu
So you may check your possibility.

You can prefer SASTRA University over CBIT. SASTRA University is ranked among the top private universities in India and it has better placements when compared to CBIT.
It also offers better education and its reviews are better.
So you can opt SASTRA University.

It will be announced tomorrow at around 9 pm.

The way to apply online is through www.sastra.edu. You need to apply before June 10th. But you also need to send a courier (post) to the contact details as in the website with your application form, JEE Mains score card (if appeared), 10th and 12th board exam mark sheet (all photocopies). One of my friends said that you need to do this or else your application will be rejected.
As there is no time now, you can contact the admin. You can also check your application status that is available on www.sastra.edu by logging in.

Yes, there are high chances for you to get a seat at SASTRA University, Thanjavur campus. As you have really good scores in JEE Mains and board exams, you have good chances for you to have a seat in good courses like ECE, mechanical engineering, etc.
Your percentile will be 102.52. The rank list will be released by June 10th (in the evening) at www.sastra.edu. With that you may check your possibility.

There are actually no separate seats for Brahmin students but there will be some preferences for Brahmin students in SASTRA University. Say, if a student is from other state and a Brahmin student from the same state have the same marks, then the Brahmin student may be given the first preference. But it is not in all cases.
Your marks decide your admission, even if you are a Brahmin student.

CEG, Guindy will be better. It is considered one of the best engineering colleges other than IITs and NITs. CEG is ranked no 8th among all engineering colleges just below the 7 older IITs. No doubt about faculty and placement too, they are very good there.

Sorry to say but you haven't cleared JEE Mains exam required cutoff. So there isn't any chance to get admission in SASTRA University for civil engineering.