Preparing for HR Competitive Exams: What Books and Formats Should I Know About?

Please suggest some books that I should read for the preparation of competitive exams like NTPC and SAIL. Which section of HR do the questions focus on? Also, please share the NTPC exam format if anyone has it. Thank you so much in advance for your help and suggestions.

Hi Seniors, I have completed an MBA in HR. Currently, I am working with a private company as an HR executive. I am interested in writing exams for SAIL, GAIL, BPCL, HPCL, Power, NTPC, ONGC, etc. Could you please provide me with study materials, reference books, and any notifications that are available? Please reply to me.

Regards, Vinu