Yar bro ik compression tester khareed lein, aur engine lete huay do wires aik bat gari ki sath lejayen. Connect comp tester and bat ground engine se laga dein and bat + starter motor ko dein
And test comp in all cylinders. It should b 175 or greater for a good healthy engine.
And tapet cover khol kar you can also see the condition plus do valve clearance test, usay idea hojayega engine kitna chala hua hai.