Colleges in Karnataka

The Architecture Department is a seperate college of MAHE. Even if it's in MIT campus, it has nothing to do with MIT.
Coming to the curriculum, the the course is totally dependent on faculties here, assignments are taken properly, excellent infrastructure, etc. Regular guest lectures are also arranged for the students.
Hostels are common for both MIT and FOA (Faculty of Architecture). Also they can be a part of various clubs of MIT and MAHE. Numerous technical and cultural clubs are there to make life at Manipal interesting.
Hope I have answered your question. Feel free to ask if you still have doubts.

You can do B.Sc(IT) provided you satisfy eligibility criteria. To do B.Sc(IT) you must have passed 12th class with Maths as one of the subjects with an aggregate 50%. Most of the colleges have different percentage criteria, very few take admission test too. But 98% colleges do not take admission test and in Christ you can take admission directly.

English Language, Comprehension Skills, Verbal Reasoning, General Knowledge, Current Affairs, Quantitative Aptitude, Numerical Ability, Fundamental Mathematics Operations, Critical/Analytical/Logical Reasoning, Data Analysis and Interpretation.
This is the whole syllabus for BBA. Kindly check it.

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

Open Universities are flexible enough. You can enroll in the program of your choice and submit an application stating your problem.
Also, there are many open universities which provide online programs. Check them out. There would be provisions in Dubai too.
All the best

Admission into IIM Bangalore is pretty much at its last stage. As CAT results were announced in January and it's April going on, so the admission are about to get over and your GMAT exam will be June. By the time, you will appear for GMAT test the institute will roll its new batch.

For BBA - Rs.80,000 per year . Total fees of BBA in Presidency College, Bangalore is Rs.240,000 .

Hi Garima,
You can send a mail to Christ University to change your interview date if possible mentioning the reason. If they accept your request then your problem can be solved otherwise you would have to go with the priority, that is you would have to choose between the two of them.
Good luck.

To apply, you should have minimum 50% marks in your graduation.
Link: https://www.shiksha.com/business-management-studies/course/executive-pgpm-indian-institute-of-management-bangalore-bannerghatta-road-115020