B.Sc Maths

Yes,
You are eligible for MCA, but you have to only give MCA entrance exam.

You should go for B.Sc in mathematics as compared to B.Sc in chemistry, as after completing graduation degree in mathematics as compared to chemistry, you have many future scope ahead, and you can get good work. And, you will increase your efficiency and skills.

As per my knowledge and my experience, you are definitely eligible for applying in Oxford College of Science for M.Sc in electric science. After completing B.Sc degree, as you have studied Electronics as one of your main subjects in your graduation degree, there is surety of getting admission.

Dear Susheel,
It would have been great if you had named the college or university you are seeking the fees for. For general information the fees range starts from 50k to 10 lacs. It all depends on the college or university you choose. Please find below link of the list of colleges across India offering B.Sc. Maths. Kindly choose on the filter of course fees to find the expected result. https://www.shiksha.com/science/colleges/b-sc-mathematics-colleges-india.

Jobs for B.Sc Maths Graduates -
Teaching
Government Jobs
Banking
IBPS
Defense, etc.

Hi, Please find the link below:
https://www.shiksha.com/law/clat-exam.

You have lots of career options after B.Sc Math. You can do M.Sc Dual degree, M.Sc, Ph.D, integrated Ph.D by entrance exam from India's best institutes like IIT, NIT etc. By giving IIT JAM.

The course specified in your question is different from the tag you have chosen. kindly specify the course name again for better understanding. Also, the college doesn't have B.Sc physics in a single subject but has Undergraduate Arts in (Arts) Single Subject which is UG Degree Distance/CorrespondenceDuration - 2 years
For all B.Sc courses under the college, click below.
https://www.shiksha.com/university/uprtou-u-p-rajarshi-tandon-open-university-allahabad-21430/courses/bsc-bc

Sorry to say, but you can't do MA after B.Sc. You should have completed Bachelors in English with at least 60%.

Yes, you can take science subjects in your B.Ed. There are various choices that you can make between subjects lists based on your previous education.
https://www.shiksha.com/teaching-education/ctet-exam