You have plenty of opportunities in computer Science field. Computer Science Engineering is a most sought after option. You have BCA, B.Tech in Computer Network Systems, B.Sc Computers as your options. The eligibility criteria for doing a diploma or undergraduate program in computer science is candidates must have passed their 12th with 50% mark in science stream. It means that candidates should have studied subjects like physics chemistry and mathematics or biology. Knowledge in Physics and Chemistry are not compulsory for computer science. But Mathematics is a compulsory subject and since you have taken mathematics in your 12th you can do your career in computer science. You should know subjects like Discrete Mathematics, Graph Theory, Probability and Statistics is required and will be useful. Since you have studied computer application and you can continue your career in computer application. BCA is a wonderful course. A candidate who have done a BCA and MCA are considered to be equivalent with  BTech.

In cs field, You will have employment in areas like Academic Institutions, Telecommunication Companies, Manufacturing Companies, Aerospace and Defence Sector, Healthcare Companies, Agricultural Sector, Retail Companies etc. On completion of this program, students can opt for various job profiles such as a Programmer, Technical Writer, System Analyst, Software Engineer, Operations Executive etc.