CBSE 12th

B.Com Is a high profile undergraduate programme aimed to create enhanced competence of career positioning tied up with opportunity to become a global professional. By pursuing this course, a student will attain conceptual knowledge and analytic skills that may help in areas of employment at various levels. Eligibility - 10+2 with 50% marks in aggregate or its equivalent examination in any stream conducted by a recognised Board / University / Council. That's the eligibility criteria of B.Com (Hons) if you don't have Maths still you can take admission in B.Com (Hons).

Your 12th Marks are good enough for getting Multani Mal Modi College, Patiala for B.Sc (Hons) in Mathematics. Application on prescribed forms for admission to B.Sc. (Hons) should be deposited with the college as date prescribed by the college or with in three days of the declaration of 12th result. Please visit college website for online registration for admission.

Usually, you need PCM or PCB for any B.Sc. So won't be very different for B.Sc. Biotech as well. Hope this helps.

There are many and it actually boils down to your area of interest, if you want to pursue careers in Defence services you can go for NDA or TES (technical entry scheme)
if you are interested in Management studies you can prepare for IPMAT
if you want to prepare for civil services you should go for B.A. The list is long, so first, decide what you want to become. Hope this helps, all the best.

In most of the colleges, Mathematics is a mandatory subject in 12th for getting admission in B.Com (H). However few Colleges like GGSIPU and its affiliated colleges admits students in B.Com (H) without Mathematics in 12th. LPU and Chandigarh University are the another Universities admits students in B.Com (H) without Mathematics in 12th. So you can get admission in B.Com (H) without Mathematics in 12th.