Bachelors

Hi,
As you are in your graduation right now. So, main focus of you should be on graduation only. After completing your graduation, you can take admission in any good colleges for diploma in interior designing. There will be no problem.
Best of luck.

Hi,
No entrance is not there.
Admission will be done on the basis of your class 12th board score or percentage.
You can fill up the application form to get admission in the college. After that, they will declare the merit list, as per the merit list you will get the option to take the admission. You can check the link for more information https://www.distancelearning.edu.in/

No, why would you choose Biomedical in PG, you can go with VLSI or some other things related to ECE which makes you get placed in good companies. And even biomedical Engineering doesn't have much scope in India.

Hi,
Please click the given link for more information on entrance exams. https://www.iihmca.org/courses-offered/
The student has to Qualify in the Common Entrance Examination (CEE) which consists of General Knowledge, General English Test of Reasoning and Numerical ability conducted in the Campus and other selected Cities by giving admission notification in leading News Papers.
Regards,
IIHMCA.

It is about to happen in June.

It depends upon the college you wish to get admission, it vary according to state and college. In general, the best four considered subject are physics, chemistry, biology and mathematics.

Students who wish to pursue M.Sc and MA programs must hold a Bachelor's degree in relevant discipline from a recognized board. For admission to Integrated B.Sc + M.Sc program, candidates must have passed Class 12 or equivalent from a recognized board with Mathematics and Physics as compulsory subjects.
Admission to PG courses available in the college will be granted based on Merit in the Bachelor's degree examination.
It has been released already. Check it here https://www.shiksha.com/college/women-s-christian-college-college-road-chennai-23597

Biology is not related to B.Sc Mathematics in any way. And, biology is not useful too in Maths. It will be helpful to improve your Marks. Hope this helps.

Mithibai College-Mumbai will release it forms for UG course in May 31, 2019 to 15 th June.