You can go for MSc or Integrated phD by giving IITJAM, TIFR-GS etc exams. You can also go for BTech if you want to do through lateral entry exams. Also you can go for MBA if you are interested in Management. Also you can start preparing for graduate level government exams like SSC CGL, UPSC CSE etc. Also you can go for MCA or if you have good programming knowledge then you can go for walk in Interviews in some companies.

These are some of the ways you can take after passing BSc.

I hope my answer helps. All the very best for your future endeavors!