• NCERT 9th Class
• NCERT 10th Class
• You should read NCERT of 9th & 10th 2 to 3 times. It will clear all the concepts because now a days questions are asked from line by line of NCERT.
• For practicing you should use Speedy General Science.
• Follow Science by Priya Ma’am Lecture.

• Quantitative Aptitude for Competitive Examination by RS Aggarwal, S. Chand Publication (Must for beginner)
• Fast Track Objective Arithmetic by Rajesh Verma
• Data Interpretation by Arun Sharma (TMH Publication) Highly Recommended
• Quantum Cat by Sarvesh Kumar Verma
• SSC Elementary and Advanced Maths BY Kiran
• NCERT Maths from Grade 6 to Grade 11
• 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.

Online Sources

• Indiabix for beginners
• Affairscloud.com Highly recommended
• Smartkeeda.com
• Abhinay Sharma youtube videos
• Daily quizzes of Adda247, Oliveboard etc
• Follow free Youtube lecture of any good coaching for practice

•  Indian Navy MR Books for Exam Preparation
• Indian Navy MR Salary, Perks and Other Benefits
• Indian Navy MR Syllabus 2021
• Indian Navy MR Recruitment 2021

Offline Sources

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

Online Sources

• Daily quizzes of Adda247, 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