Hello Dinesh,
First, I'd like to tell you that Aerospace Engineering is a combination of astronautical and aeronautical engineering. Hence as a given, it will be harder than aeronautical engineering.
While there are a few colleges in India that offer both courses, the scope after these courses is hard. Most of the time, you will require connections to get through into even Government companies like DRDO, HAL and HAL and sometimes they have their own entrance exams as well.
There is more scope outside India but it is harder to get a work visa for non STEM subjects in USA. Getting a work permit in Europe is extremely difficult as well.
Many aeronautical engineers move into managerial positions so as to secure jobs.
There are opportunities for both courses, mind you, but I would suggest that such niche courses be taken only if you have a very strong desire and the required aptitude .
Candidates can check B.Tech Cut off for Top IITs & NITs here.
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