B.Tech

Sweet is unlikely that you get an government college for b tech in CSE with 70 percentile in JEE main because most of the NITs and IIT require higher percentile.

But you can look for some private universities mentioned below:-

• LPU
• Nehru Institute Of Technology
• Chandigarh University
• Assam down town University
• Bennett University
• Glocal University
• Pondicherry Engineering College
• SAGE University, Indore
• SRM University

Thank you 

.No, it is unlikely that you get computer Science branch in IIIT in any IIIT with 86 percentile in JEE Mains whether you belong to OBC NCl category.

You can check other colleges like NITs or GFTS, but it is unlikely that you get computer Science branch easily in those also 

Thank you

Once you apply and pay the fee for SNUSAT (Shiv Nadar's entrance test), you'll find model papers right on your dashboard. But if you want extra prep, Google :

Shiksha's download section
Just type “SNUSAT sample paper PDF” and boom—you'll find loads of practice sets

While it's difficult to say definitively, your chances of getting a seat in SASTRA's B.Tech Data Science and Business Analytics programme with an 88% in boards and a 60% in JEE are not very high, but not impossible. SASTRA considers both 12th board scores and JEE Main scores for admissions, but JEE performance is a significant factor. With 88% in boards, you have a good chance of getting an A+ grade, but a 60% in JEE (which translates to roughly a low percentile) is a concern. 

For BTech Computer Science, it's INR 30,000 per semester, and the same for mechanical engineering.

If you are interested in M.Tech course after B.Tech course and your branch is civil engineering branch then you can give the Gate Entrence examination for taking admission in government top colleges for M.Tech course 
And some other exams name is given as following 

1 BITS HD 

2 Karnataka PGCET 

3 OJEE 

4 TANSET ( Tamilnadu Common Entrance Test) 

5 CUCET (Central University Common Entrance Test)