Computer Engineer

Hello Ajinkya,
You can go for certification courses offered by Oracle:
DBMS
Core Java
Advanced Java
If you're interested in networking you can pursue CCNA (Cisco Certified Network Associate). It has a great value and is valid for I guess two years. So, you may want to apply for it in your final year of engineering only.

It depends on which institute you chose and in which state. If you talk about Kerala it also depends on which college you apply to and what your category is.
For more details please visit:
https://www.shiksha.com/b-tech/resources/keam-cut-off-predictor#&ui-state=dialog

It is a kind of a myth, because if you have knowledge about your field or you are good at program hacking, you can make your career more effective.
All the best.

You should choose PCM with IT and English. Prepare hard and join any elite college to pursue software engineering.

Majority of first generation entrepreneurs in India are IT professionals who have created innovative software products and launched their e-commerce services. You will definitely learn technical skills to become an entrepreneur if you do B.Tech CSE or B.Tech IT. You can do short courses on management subjects to do your own business.

You have the following options to become a software engineer:
(a) B.Tech CS/ IT
(b) BCA-MCA,
(c) B.Sc-M.Sc CS/IT.
(d) Diploma in computer science from polytechnic
(e) Computer courses
You are advised to take physics, chemistry and maths as a subject for 10+2 and work hard to take any of the above mentioned path to fulfill your dream of becoming a software engineer.

You have not shared your subjects. If you have physics, chemistry, maths and computer science subjects, then you are not required to study any thing else now to become as software engineer after 10+2 stage. If you do not have CS as a subject then you may learn any one computer language such as C+.

You have to qualify GATE entrance exam to get admission in good colleges for M.Tech.