dear harish
can u let me know in which part u are facing difficulty – understanding , problem solving or concept based ques .
u have 2 years of time , so, start with besic ncert and study that twice , as once noone can understand it . and then take out any one ref books or your oaching material to get some extra knowledge and understanding about that topics .
after that ask here in case u have any kind of doubt ,
after clearing of doubt , u can start with practicing prev year ques ,
HOPE IT CLEARS
REGARDS