Hello Aman,
Without a thought, Dual-Degree is a better option as compared to just B.Tech. B.Tech + M.Tech takes 6 years where Dual-Degree program gives you both degrees in 5 years span. IIT Buvneshwar ranks at number 9 whereas IIT Dhanbad ranks at number 19. So, by these 2 points pursuing Dual-Degree from IIT Bhuvneshwar is a better option as compared that just B.Tech from IIT Dhanbad.
All The Best
Candidates can check B.Tech Cut off for Top IITs & NITs here.
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