Presently I am in 12^th std(cbse board).I did not studied 11^th std properly.Is it possible to get a good rank in NEET/AIIMS 2017 if I start my preparation from today.I have only 9 to 11 months in my hands.

@ karishma 
yes, u can . but from now , focus only on study ./ nothing else , 
and also give some time everyday to revise the 11^th part also , as they are highly important for NEET and aiims . 
and start doing the aiims previous year papers to gain the confidence . 

u can check out askiitians self study package and test series , these are extremly helpfull . 
practice as much as u can . 
donot loose focus , as they are imp. in this p[eriod of time .. 
ALL THE BEST ..