Hello student,

No, Both the courses are different from each other .

B.Sc computer science:

It is a bachelors degree course in science along with an additional subject i.e computer science. In computer science you will study some programing language like C,C++ etc.

BCA:

BCA reffers to a professional course in computer field. The course is completely computer dependent. As in this course all subject will be computer related along with some basic subjects like maths , English  etc.

Hope it helps. 

Thank you  :)