Since you are in third semester of your BCA course, you are advised to follow the syllabus closely as provided by university and in your syllabus you may get detailed studies of various tools such as microprocessor, algorithm, Java language, C++ etc. Familiarity with these modules will equip you with success in the computer profession. With the sound concept in such languages, you are likely to achieve a grand success in your examination.
There are a lot of demands of BCA passed out students in multinational companies such as Wipro, TCS, Infosys, Tech Mahindra etc and apart from it, you may appear for jobs of Probationary Offiers in Banks, job of computer - teacher in a school. If you are interested to crack Civil Services Examination, you can attempt the same like any other graduates. However, scoring of more than 60 percent marks will land you success in different fields.
There are numerous languages such as Java, Oracle, C++, SAP etc and your rate of success depends upon the specialisation of any one of such languages.