I have completed my degree 2rd year in the year 2015 and now I want to complete my degree 3rd year my stream was B.Com. Can I do this year?

No, it is not possible for you to continue your third year because you stopped with your second year in 2015. It is a long gap of 8 years. Each course has its own length of time. Anyway, if you can just check with your university if they offer any terms or conditions in this regard. But the chances