CBSE 12th

BA doesn't require maths as a subject. B.A. is a 3-year undergraduate degree offered in India, the minimum eligibility for admission to which is passing in Intermediate or 10+2 level from a recognised board or university. The course is generally offered in Liberal Arts Humanities.

Yes, you can apply in BHU for B.Com:
https://www.shiksha.com/accounting-commerce/course/b-com-hons-banaras-hindu-university-varanasi-30928

Just go through this link and fill out the required details:
https://www.shiksha.com/college-predictor

There are a lot of private Diploma & certificate programs available on subjects like Dietitian & Nutritionist in the market. However to get mileage out of this as a career I would advice you to enroll for a Bachelor programme in Home Science and seek specialisation in F&N. Post it you can always explore a string of such private courses.

Most courses like B.Sc. B.A. B.Com BBA BAF, B. M. offer admissions based on 12th result linked to merit. Keeping in mind your interest areas and percentage scored in HSC you can select a college & course.

The decision would be based on your interest areas and long term career plans. Since you are a Science student you have the option of exploring career in Pure sciences, applied sciences, Arts, commerce, media, management, performing arts, liberal arts, medicine, etc. , Many of these course will require you to appear for an entrance test, so you need to explore it accordingly. A person usually does well on the career front if he/she joins a course which it aligned to ones interest areas & passion.

https://www.shiksha.com/mba/cmat-college-predictor
Here is the tool which you can use to get a good prediction about the college according to your score range.

Since, most of your details are mentioned in marksheet, someone may contact you regarding it. If not, You can apply for a new marksheet in your respective school. They will guide you with procedures and your new marksheet will get issued in not more than 15 working days.

Your question is not enough to answer. Please provide details about the course and college for which information is sought.

The eligibility criteria of B.Com (Hons.) is ; An aggregate of 45% marks in 10+2 examination. The applicant must have studied and passed Mathematics/Business Mathematics at the qualifying examination for admission to B. Com. (Hons.). So, Math is compulsory at 10+2 level at Hansraj College.