Hi
You cannot pursue both the courses simultaneously. You can take BCA and MCA in a dual degree or integrated course and get academic and financial benefits.
In an integrated degree of BCA+ MCA you save one year hence he related costs of one extra year of learning.
In dual degree of BCA + MCA you get the benefit of the fee structure at the time of admission to the lower degree. The fee is fixed for the whole course.
In such schemes you know the faculty well and can have a better interaction.
You know the rules of the university.
You become an interim part of the university and become a leader in many of the events as you are an old student of the university.
You get more chances to participate in the activities related to industry.