B.Com

Hi Suman,
From which university you want to do your MBA ? Reply so that I can give you necessary information.

Check it out on the college's website.

Yeah, Kolkata St. Xaviers is well preferred for BCom. Other Xaviers are also good across India. Few other colleges are also there that provide good class BCom. Use https://shiksha.com to check out colleges according to your prorities.

They say the forms will be out after class 12 results. ISC results are already out; so probably after CBSE results they will start the admissions. Keep checking the college's website.

if your soul aim is for LL.b then do an integrated 5years course it will save your 1 year

B.com genral is best

Here i listed the subjects name for B.Com course.
In 1st Year:
Financial Accounting
Business Mathematics
Business Economics
Business Management
Business Communication Skills
Basics of computers
Business Environment
In 2nd year:
Corporate Accounting
Business Statistics
Business Regulatory Framework
Corporate Law
Macro Economics
Marketing Management
Optional Subjects in 2nd Year:
Fundamental of Insurance
Human Resource Management
Production Management
Computer: Application of Information Technology and Business
Business Ethics
Banking and Banking Law
Basics of Retailing
Best of luck.