But sir according to previous year cut off in 7th or 6th round there was option in mining machinery or metallurgy in iit dhanbad or iit bhu . I want to confirm whether this year would be the same situation or may change.

Yes. As I said. Metallurgy and mining are one  of the least preferred branches. And we can't predict the cutoffs. Last year, may be no one took the risk of taking mining and metallurgy. If people consider them this time, you might not get a chance. Think twice before opting for such branches. IIT Brand matters, but if you don't like the branch 4 years will be a sheer waste of time. Hope for the best