Colleges in USA

Yes, NLSIU is a national university.

Hi Jahnavi,
To apply for undergraduate courses in Stanford, you must take the SAT or ACT with writing as part of the application process. In addition to these, you must have excellent grades in your 11th and 12th and be an all-rounder. The university you are talking about is the world's most selective universities and admits very few students. Check here, read the requirements, see the kind of students they prefer and prepare:
https://admission.stanford.edu/apply/freshman/index.html.

Hi Augustya,
All universities in USA offer financial aid, and its on merit. You will be automatically considered for scholarship at the time of admission. Since these are on merit you must have a good profile, good grades and apply early. Check university websites, see the deadlines and follow the timelines. It takes a year to prepare for the application process. So prepare early. Some of the best includes
MIT
Georgia Tech
University of Pennsylvania
UCLA
UC Berkeley
University of Princeton
New York University etc.

Hi Abhishek,
If any business schools mention they require work experience for their MBA programmes, it means you will have to get work experience. After your B.Tech, you must get a job and take the GMAT before you qualify for MBA abroad including USA. There are some options and you have to search. If you have an exceptionally good profile, you may be considered by the good universities. Or look for MS in management courses.

Hi Harshit,
All of these are world's topmost universities and students are expected to be very academic in nature. 75% is the minimum recommended. The more percentage you have, the better it is.

Hi Vikashini, before I guide you please check here for all undergraduate majors and specializations, visit the engineering page to view the engineering programs
http://www.nyu.edu/admissions/undergraduate-admissions/majors-and-programs.html
Also check the admission requirements for the programme you want to study. Check here for applying
http://www.nyu.edu/admissions/undergraduate-admissions/how-to-apply/all-freshmen-applicants.html