Can I shift from correspondence to regular B.Sc in 2nd year?

No, it is not possible to do this currently Either you complete a degree from a regular course or from distance by doing all three years in the same mode. BUT You should check with your institute if you can shift from correspondence to regular B.Sc. In your 2nd year.

You should check with your institute if you can shift from correspondence to regular B.Sc in your 2nd year. Most institutes do not have this facility, but it will be best to check with your institute.