Does the language section of Allahabad University for 3-years contains questions only on English or in Hindi and English both?

Sure, here are some of the top colleges for 3-year LL.B. Programme in India: Faculty of Law, University of Delhi, Delhi Government Law College, Mumbai National Law School of India University, Bangalore Symbiosis Law School, Pune Indian Law Society's Law College, Pune Jindal Global Law School, Sonipa

Your chances are there. I would suggest you visit the official website of Allahabad University to get a better idea.

Yes, you might get admission. All the best.

Yes, you are eligible for getting main campus, as the 2017 cutoff says that the candidates with 142 marks were eligible for getting admission in main campus.

You have a very Brilliant rank so you have a greater chance of getting the main campus