Colleges in USA

The eligibility is graduation in the relevant field with 50%marks, if you meet the eligibility criteria, you can go for admissions.

UK based Colleges give admission just on the basis of IELTS score to Indian Candidates. So Would recommend you Ireland for same. Also, better opportunities than USA.

Yes, many colleges provide scholarship after scoring high in 12th. As it refers if you are general or reserved. you can get a scholarship if you apply for the national scholarship program.

You can join any Aircraft company where you can work as technician, aircraft management because of increased air vehicles, along with the defence like airforce where you can work as air fighter pilot. You can attend any mechanical interview in your college, and if there are interested in you may get place. You can get job in ISRO, and so many.

I don't know about the reservations, but for admission in a good NIT, you don't have to wait for the JEE Advanced score, you can get admission to the college by getting at least 250 marks in the JEE Mains exam.

The computer science branch of engineering is very well known for placements in Chandigarh university though other groups also have a good placement record. So, if the only concern is placement then CSE branch will be good.

The candidate should be 12th pass to take admission in BTS course in IGNOU.