Good Morning

Hope you are absolutely fine, as per your query to get admission in BCA course you can give some entrance examination or you get admission in merit based also throughout India, there is no official exam conducted by government to get admission in BCA, there are some university who conduct their own Entrance exam like SET, IPU CET, UPSEE, and BVET etc. you may get admission through 12th marks, you must have passed 12th with at-least 55% from any recognised board.

For more information about BCA checkout given link below:
https://www.careers360.com/courses/bca-bachelor-of-computer-applications

Hope you found it helpful
All the best!!!