@ harsh
i would recommend the MTG bitsat explorer and Arihant Bitsat explorer for that , they both are excellent books , and first of all complete your ncert and understand each and every besic concept in them , after that use some extra books like concept of physics by h c verma and physical chem by o.p tandon etc , and then start practicing the previous year bitsat paper avaliable at askiitian website , that is so important , and then simoultaneously practice the MTG exploerer , u can refer to the askiitian self study package for that , its awesome and explain each and every concept precisely .
HOPE IT CLEARS YOUR DOUBT
ALL THE BEST ..