There are many options after BSc computer science. 

• If you want to continue your studies then you can go for Masters in Computer Science. As you have computer background then you can also go for Master in Computer Applications. 
• If you have passion for business then you can give entrance exams like CAT to get admission for MBA in top IIMs across India. 
• If you want to do job then companies hire many graduates in Computer Science. So you can apply for the same. 
• If you want to work in government sector then you can give exams conducted by UPSC for IAS,  IPS, etc. If you want to join Indian Army then there is also a entrance conducted for the same. 
• If you want to do teaching then you can give respective exams an apply for the same in various schools,  colleges and universities. 

If you still have any queries feel free to ask in the comment section down below.