Study Abroad

You can pick an OS between Windows or Ubuntu. As majority of Indian colleges operate on Windows, there are few colleges which operates on Ubuntu. I haven't seen any college operating on Mac. So, it is better to stick with the technology used in your college. If you want to learn programming languages which you will be studying in your BCA course then you can check out this app "BCA - Course Programming" which is specially designed and developed for BCA students and is available on Google Play Store. It has programs and assignments of languages like C, C+ and Java with their outputs. You'll be studying these languages in your 3 years of BCA.
https://play.google.com/store/apps/details?id=technark.bca_courprogramming

Hi Ashiqu,
This is not the problem that you want to change your stream. However, the question is that if you are eligible for University of California or not? Certain things matters like, your graduation CGPA, Work experience in relevant field (which is very important), employers brand value, extracurricular etc. These are some of the broad parameters to judge the candidacy of the Student. Apart from the general procedure, I suggest you to go on their website, and check about the international alumni. Analysis their profile. Doing this will help you get clear picture about what you should to have in your profile. Hope this helps. Ask any question at any time. Upvote the answer if you feel satisfied. Good Luck.