Science

You can't get admission in the third year of B.Sc directly and also with this kind of desire. You must attend the regular classes to complete your graduation in chemistry honors. Without practical classes, you cannot learn anything. So, no college will allow to do this.
Try to attend regular classes

Hi Kanika,
As you have scored 67% in class 12th board, so you are eligible to take admission in SD College, Chandigarh. I will suggest you to apply for this college. Although cutoff goes high, so you need to wait till the last round.
Best of luck.

Yes, you can take admission in BBA with 78% marks in 12th ISC board.

You can't get admission on the basis of your merit of class 12th until and unless you pass all the subjects of 12th. That's the minimum eligibility.

No, there is no chance of getting admission at DU in college of arts and commerce at this percentage in class 12th. You need at least 90% in class 12th for getting admission here in OBC category.

BCA is a better option that B.Sc IT because it would open up your chances of jobs a lot more.

Refer this link for more information:
https://www.shiksha.com/nursing/course/b-sc-in-nursing-avadh-institute-of-medical-technologies-and-hospital-lucknow-324123?rf=searchWidget&landing=clp

Hi,
B.Sc. Agriculture and B.Pharma courses - The test is conducted on 14th to 27th April 2019 through online and offline mode. Candidates those who qualify the entrance test will be called for the counselling.

For doing BSc. in food technology the criteria is the candidate must have passed the 10+2 level with PCB with aggregate of 50%. As you are from obc category and possess all the verification documents you will get relaxation under sc/obc quota too. Some colleges take admission through entrance exam

Hi Pradyumn,
For M.Sc in astrophysics, these are the best colleges in India:
https://www.shiksha.com/science/colleges/m-sc-astronomy-colleges-india