CBSE 10th

Yes ; in B.Com you can easily take admission
For further details and fees you have to visit college once
because every college have different regulations and different fee structure.
All the best

Yes, it is possible that after class10th, you can do fashion designing course.

Hello! Well, nothing can be said with complete surety but a score of at least 99 percentile should be sufficient to get an interview call from some (if not all) of the B-schools mentioned above. Good luck!

Hello, at 100 percentile in CAT you will surely get a call from FMS. But the final selection depends upon your performance in those interview rounds.
Good luck!

Use rank predictor to get a rough idea of your rank and percentile.
https://www.shiksha.com/b-tech/resources/jee-main-rank-predictor
Then, use the college predictor to know about the colleges:
https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor

Eligibility Criteria for admission in Diploma in Audio and Music Production - Candidate must have passed 10+2 from a recognised board.

Don't take instant decision. You have sufficient time for thinking.
IIT Bombay
IIT Madras
IIT Kanpur
IIT Kharagpur
These are the top colleges of aeronautical engineering. So, well in your +2 exam and after that give IIT exam.

Eligibility Criteria for admission :
Candidate must have passed 10+2 from recognized board.

Foreign universities have their own admission process. Your scores are decent. Shortlist few colleges in Germany. Checkout their course and syllabus. Select few colleges where you would like to apply. Prepare for the entrance exams which they consider. Do well in exam. Proceed with admission process. Every college will have a different criteria for admission. You need to check it on their website. All the best.

D.Ed: Eligibility
Listed below are the minimum criteria which candidates interested in pursuing the course are required to fulfil, in order to be eligible to apply for the course. Successful qualification of class XII from a recognized educational Board. Preferably, Humanities subjects as the main subjects of study at the 10+2 level, and a minimum aggregate score of 50% (45% for SC/ST/OBC candidates). The minimum age limit is 18 years and upper age limit is 36 years. It is relaxed by three years for OBC and five years for SC/ST candidates.