• Lucent’s General Knowledge by Vinay Karna , Manwendra Mukul , Sanjeev Kumar , Renu Sinha , R. P. Suman ( For preparation of static part) 
• Manorama Yearbook 2021
• Advanced Objective General Knowledge by Arihant Experts
• NCERT Books of Class X, XII- History, Geography, Economics

Online Sources

• Daily quizzes of Adda247, Gradeup, Oliveboard etc
• Follow Daily free Youtube lecture of any good coaching
• Monthly and daily capsules of Adda247, Anuj jindal or any good coaching for preparation current affairs
• Read daily news

• Word Power Made Easy by Norman Lewis (Good for building up vocabulary)
• Newspaper- The Hindu, The Economics times, Business Standard, Indian Express for beginners
• Objective General English by SP Bakshi
• Quick Learning Objective General English by RS Agarwal
• How to Prepare for Verbal Ability & Reading Comprehension for CAT by Meenakshi Upadhyay and Arun Sharma
• The Pearson Guide to Verbal Ability and Reading Comprehension for CAT by Nishit Sinha
• Better English by Norman Lewis
• High School English Grammar and Composition by Wren and Martin

Online Sources

• Indiabix for beginners
• Affairscloud.com Highly recommended
• Smartkeeda.com
• Follow Daily The Hindu Editorial analysis on Youtube of any good coaching

• Quantitative Aptitude for Competitive Examination by RS Aggarwal, S. Chand Publication (Must for beginner)
• Fast Track Objective Arithmetic by Rajesh Verma
• Quantum Cat by Sarvesh Kumar Verma
• Comprehensive Guide for Quantitative Aptitude by Disha Publications
• Quantitative Aptitude for Competitive Examination Paperback by Abhijit Guha
• Magical Book on Quicker Maths by M Tyra (Highly suggested)
• How To Become A Human Calculator by Aditi Singhal ( Must for those who wants to improve calculation speed.
• How to Prepare for Quantitative Aptitude for CAT by Arun Sharma 
• Quantitative Aptitude Quantum by Sarvesh Kumar
• Quantitative Aptitude for CAT by Nishit Sinha

Online Sources

• Indiabix for beginners
• Affairscloud.com Highly recommended
• Smartkeeda.com

• A Modern Approach to Verbal & Non-Verbal Reasoning by R.S. Aggarwal for beginners
• A New Approach to Reasoning Verbal and Non-Verbal by B.S. Sijwali and Indu Sijwali
• Analytical Reasoning by MK Pandey (Highly Recommended)
• Wiley’s Reasoning ability and Quantitative Aptitude
• Data Interpretation by Arun Sharma (TMH Publication) Highly Recommended
• How to Prepare for Logical Reasoning and Data Interpretation for CAT by Arun Sharma
• Logical Reasoning and Data Interpretation by Nishit Sinha

Online Sources

• Indiabix for beginners
• Affairscloud.com Highly recommended
• Smartkeeda.com