hello shweta 

you can do mba from both of the courses ,bba and b.com . you just need to qualify the eligibility criteria of the entrance exam for mba . for mba admissions generally entrance exams are conducted so you can get admissions by clearing them . BBA seems quite helpful but  there is no prob with b.com too .cat is one of the most famous exam for mba .check out this 

https://bschool.careers360.com/articles/cat-eligibility-criteria

best wishes