I am 30 years in age and I am doing B.Sc from IGNOU. What are the career prospects after doing B.Sc?

If you want, you can pursue Master's degree and can get a good opportunity in the teaching field and you can get a job in many reputed companies also.

You can pursue either M.Sc to continue studying in the same stream and then later pursue Ph.D or pursue an MBA in your desired specialisation that you think will help in your career.