Should I go to IIT Patna CSE or drop this year?

It's illogical to consider giving up on such a good opportunity of joining IIT Patna CSE and taking a drop year. Don't let the fact that IIT Patna is a second-generation IIYT dissuade you from joining it. CSE from any IIT is a golden opportunity and should be considered without any hesitation. 

IIT Patna has been here since 2008 and has grown a lot ever since its establishment and is still expected to improve every year. The placements of this branch in itself are a testament to its excellence. 

Additionally, the students of this branch are achieving great heights in all the competitions and have been offered paid internships in various companies and top foreign universities. The environment is academic-friendly promoting research and other opportunities. The seniors are very dedicated to guiding you in every step. 

I dont think taking a drop year is a wise decision as there is no certainty of improved rank. So, its better to join the CSE branch of a new IIT than to take a drop year unless you are certain of a better rank.