Is it a good choice to pursue B.Sc from DU? Will I get good career opportunities after completing B.Sc from DU?

You can go for teaching, if you will do M.Sc, and you can prepare for IAS, IPS exams side by side. You can go for MBA ahead. All the best.

Doing B.Sc and M.Sc from DU is equivalent to doing B.Tech from a reputed university. So, best of luck and try hard.

You have competitive exams like SSC, Bank PO, IAS, RBI and various all other competitive exams. Pursue higher studies if you love maths and there is lots of institutes like ISC, CMI, JNU , Jamia, ISER, IIT ,NIT and DU as well . You can google it or ask from seniors or teachers. That will really help