Is it worth to pursue B.Sc or not?

Try to go for a professional B.Sc course rather than B.Sc in PCM/ life sciences. Though chemistry hons. is also a decent option.

If you dream to study or work in engineering, then it is not worth taking. As most of foreign universities demand for four year engineering, you have to do M.Sc also. In India, B.Sc has good scope and you can pursue.