Science

At graduation level admission is based on class xii marks. only few courses like bba, bca, and some colleges go for entrance test. there should be no problem. you can fill the form for commerce stream

Yes. maths is required for MCA. but there are institutes that offers 6 months bridge course to complete class xii standard maths

There is no need to change your stream in order to pursue mba in future. Dont mix up management and commerce. Go with your desired stream in grad. Then go for mba from a good college. All the best.

It will depend on your preferences. If you want to do applications programing then BCA and BSc IT are good. If you have Maths background and want to understand theory of Computer Science then become system programmer then BSc CS is better.

Dear Akshayaa,
If you are looking for the best colelge for BSc in Interior designing, then below is the top 10 colleges for the same:
http://education.sulekha.com/top-10-interior-design-schools-in-india_600786_blog

Dear Anuj,
Score good and wait for the cut-off to be out from Delhi University. See which college accept the percentage you scored. Then visit the college and do the admission formalities to get into the Delhi University College.

The best colleges to get into for BSc in Physics are listed below:
1. Hindu College
2. St Stephen's
3. Hans Raj College
4. Miranda House
5. Venkatesawara College
6. Gargi College, Delhi
7. Ramjas College
8. Maitreyi College, Delhi
9. Sri Ventateswara
10. Kirori Mal College
However, you will have to check the cut off list, whenever it will be out.

For colleges in Delhi check this
https://engineering.shiksha.com/msc-environmental-sciences-in-delhi-ncr-categorypage-2-65-1439-0-0-10223-1-2-0-none-1-0
For Bangalore check this
https://engineering.shiksha.com/science-engineering-colleges-in-bangalore-categorypage-2-1-1-0-0-278-106-2-0-none-1-0