IIT-BHU is one of the most reputed colleges in India and is a real IIT. This question might have popped up because IIT BHU got converted from IT BHU to IIT in 2012. But, even before that, it pretty much met the standards of IITs. Students who got admission, even before 2012, had qualified JEE Advanced. Below mentioned points will back up the above statements.
The points, as mentioned above, very well prove that IIT BHU is very worthy of being an IIT.