One of my friends studies at IIT Dhanbad, and according to him the coding culture of IIT Dhanbad is developed and good. The following points are based on his experience at IIT Dhanbad:

• CSE students conduct several coding workshops and students join coding clubs, and associations year-round. 
• The institute has the Association of Computing Machinery (ACM) that organizes seminars, lectures, competitions, and presentations if you are interested in coding. 
• It also has Cyverlabs Club with different branches such as Web Development, Machine Learning, Arduino Development, etc. The club is headed by experienced seniors of IIT Dhanbad. 
• They also help and train students in gaining computing skills. 

Therefore, if you are thinking to join IIT Dhanbad then you can go for it. It has a great coding culture. Also, the institutes organize various coding events and competitions for students all around the year which helps them acquiring a good knowledge of it.