CBSE 12th

The safest percentile would be 95+ for you to get into IIMs.

Yes, you can easily get this NIT for CSE under the category seat easily.
Go ahead.

For that, you have to score a minimum of 45% in class 12th and at least 150 marks in JEE Mains in order to get this college.

No, you won't be able to get admission in this college at this score, but yes, you can get admission in other streams of this college.

Yes, you can easily get admission in this college but for CS branch, you have to wait till the last round of counselling.

Yes, there are many scholarships on the basis of income and merit that can be availed on the basis of class 12th result. One of them is inspire scholarship which can be availed if you are in top 1% of your respective board and pursuing a pure Science course. The award received is 80k per year, of which 20k is for a summer research project.

Some Colleges are:
Indian School of Ethical Hacking
All India IT Association.

For taking admissions, there you need to crack the IIT exam. Since you have a fair percentage in class 12th, you are eligible to give the IIT exam.

Well, there are many kinds of courses which could give you jobs with satisfactory salary and even can make you something just like an engineer, architect, doctor, singer or anything. Most importantly you have to take time and give a thought to what your prior interest is. Analyze, choose the course accordingly and start preparing for it.

ACCA is the best option it is equivalent to CA, but it's degree is acceptable in 180+ countries, so you can get a job in any of the country in the world with this degree and this course is very easy.