Hi

You can go for BCA after your 12th with biology as a subject.Eligibility criteria is as follows:

 50% aggregate marks in 10+2. 

Age must be atleast 17 years.

Some popular universities are where you can pursue BCA:

Lovely Professional University- Punjab,

Hansraj College - Delhi,

Loyola College - Chennai,

St. Joseph's College of Commerce - Bangalore etc.

You need to clear their entrance exam at first and then after you can take admission.I would say if you have an interest in Computers go for the BCA course as you will have to do programming using C/C++/Java ..etc.

All the best.