I am a dropper so how should i prepare for the exam. i am yet to start my prepration. my targets are iits or niits.i have got 88.4% in cbse and i cleared iit mains by getting 109 marks. so i wanted to ask that what are my chances of acheiving my goals?

And how should i prepare for that ?

You should now stop your practice and start your prepration soon. It will be better if your join any institute, because that will help you in increasing your level as well as keep your preparation strong till the end. As you have already cleared the mains so therefore, its suggested to focus on problem solving skills more for this year. Thanks.