Computers & IT (Non-Engg)

Yes, you are eligible. You should go for CEH course.

Well, you can start with anyone, either of Ethical Hacking or CCNA, since they are different areas but I personally would advise you to know basic networking at least before you go for EH or CCNA.
EH has a very good exposure presently and high demand in job market rather than CCNA.

Hi,
IF you had mathematics in 12th then you are eligible for BCA.

There is a lots of chance for white hacker. Cyber security is the most booming area nowadays. So, it is a better opportunity to start career. You can work as VAPT, participate in bug bounty, do CEH of entry level to pass for all. Side by side, you can complete your Master's degree.

In Pune, Arizona Infotech is a good institute for Security course like CEH, CHFI, ECSA, etc. There is no need but doing it is always better.

Your basic degree is not aligned with professional courses you are planning to do. You will always face competition from engineers in your chosen field. You are advised to do basic course on computer technology to evaluate your understanding and comfort in learning computer hardware before you take specialist courses.

It's very basic and high level understanding of ethical hacking, but to become a professional you need to get certified by CEH or CISSP.