CBSE 10th

You can either go for mechanical or electrical engineering.

Yes you can if you score very well in written exams and GD/PI

Hi Neeraj! For getting a call for WAT - PI, you need to score around 66 percentile in CAT. Then , as per your percentile and performance in WAT-PI, you will get selected for studying in IIFM.

If you are in need of job quickly due to personal reasons then undergoing diploma in a Polytechnic is a advisable option. But if you are not in hurry for job you may follow typical education path of +2 and then graduation.

Without applying for entrance test it is impossible to get admission to MBA in SIBM so you will have to try next year now

To become a software engineer, you need to persue BTech CSE /IT. To ve eligible for BTech, you need to appear for JEE Mains.
http:// jeemain.nic.in

Hi
It purely depends on what you wish to pursue further and in which country. CAT is for admissions to management institutes in india for courses like mba, PGP, pgdm etc.
GMAT is international standardized test for business management colleges for post graduation accepted in most of the countries.
GRE is for master's in other subjects than management for post graduation courses again abroad.
TOEFL/ IELTS is the English language proficiency test accepted in almost every country abroad.
So ideally , you will either be taking GMAT/GRE and TOEFL/IELTS to apply abroad.