If you find a of R.S. Khurmi's Engineering Mechanics on Google Drive, download it immediately. It is a fantastic reference tool to have on your laptop for quick problem-solving.
While the Khurmi PDF is gold for objective exams, you might need supplementary books for concepts.
If you need study material without violating copyright:
: Covers the basics of science and engineering mechanics, fundamental units (SI system), and the composition and resolution of forces.