my obc rank is 3017 which iit and which branch I will get
First of all congratulations on securing 3017 obc rank in jee advanced 2020. You have secured a very good obc rank and definitely you can get many good iits.
As per seeing last year cutoff closing ranks for final rounds soem of the iits that you can get on basis of your ranks are :-
Iit dhanbad (chances to get chemical engineering and civil engineering, easily get engineering physics, or mining engineering)
Iit dharwad ( mechanical engineering)
Iit ropar ( chemical engineering)
Iit bhilai ( mechanical engineering)
Iit bhu ( metallurgical engineering)
Iit delhi ( textile engineering)
Iit gandhinagar ( chemical engineering, materials science)
Iit guwahati ( biotechnology)
Apart from these good iits you can also get many other good branches in new iits like you can easily get seat in iit jammu or iit goa or iit palakkad, etc.
Also in iit madras you can get dual degree in biological engineering.
Also check out our jee advanced college predictor tool to get an appropriate idea of iits that you can get on basis of your jee advanced rank :-
https://engineering.careers360.com/jee-advanced-college-predictor?icn=QnA&ici=qna_answer
I believe having a OBC Rank of 3017, best option will be pursuing Metallurgical or Material Science amd Engineering at either of the following IITs
IIT BHU IIT Hyderabad IIT Indore
IIT Bhubaneshwar IIT Gandhinagar
Metallurgical Engineering is a very structured course and provides you with opportunities in Core , Non Core and well as Research Sectors. Metallurgical Engineering is something between Chemical Mechanical and Mining Engineering and gives you a taste of all three.
If you want to study Circuital Branches like CSE EE or EC best options for you would be choosing Electrical or EC at either of the very new IITs, Dharward, Goa, Palakkad and Tirupati. However that is not advisable since you have excellent scope at the older IITs or particularly newer ones at Hyderabad and Patna.
For more information and rank prediction do follow the link below
https://engineering.careers360.com/jee-advanced-college-predictor?icn=QnA&ici=qna_answer