I am confused whether to become neurosurgeon or aerospace engineer..I want to know which has more scope?

There are two resources that I recommend to help you figure out the types of careers you should go into. One is the Meyers-Briggs Type Indicator (MBTI). This measures how you (as a person) take in information, how you process it, and how you output it. Engineers fit into certain categories of personality types. A good book to read about this is Do What You Are: Discover the Perfect Career for You Through the Secrets of Personality Type by Paul D. Tieger and Barbara Barron-Tieger. Your school career center may know how you can take the MBTI assessment, and may be able to provide help in interpreting it. Even without taking the assessment, the book can give you a good idea of the personality type you have, and you can read about the kinds of careers that people with that personality type do well in.

The other resource is Strengths Finder 2.0 by Tom Rath. The cost of the assessment is built into the cost of the book, so if you get a used one, be sure it has an unused access code. The basic idea of this book is that you come into the world with certain strengths, and it won't make much difference on how hard you work on your weaknesses, you will get a lot more results by putting the same effort into working with your top five strengths. Page 9 says, "You cannot be anything you want to be, but you can be a lot more of who you already are. " It does not give as much advice about what careers to choose, but if your strengths are different from those that are supportive of engineering, or supportive of being a doctor, you should look elsewhere for a career.

I am surprised! These are two different careers with very different paths. You could become an aerospace engineer in less than five years; however it would take you over 12 to become neurosurgeon. I think you need to research both careers very well and afterward let us talk.