Hello Shivani, Yes there is the entrance exam for BCA, normally it held every year. Different college conduct exam on different month (April/May/June) which contains questions related to Aptitude, Logical Reasoning, General English and General awareness.

Example of List of dates for BCA entrance

https://www.shiksha.com/it-software/articles/top-bca-exams-in-india-blogId-13696