Will I be able to take lead of those who are ahead of me? I am in class 11th and I am lagging in many chapters.

You still have the time and there is no need to worry at all. Consistent efforts and proper time plan will help you perform better in your studies. Identity your learning style i.e. how you learn better. Is it by doing, by drawing or by reading . Also remember that whatever you study you must pract

You don't need to worry. Firstly, focus on the subjects and the chapters where your are weak and try to pull it up. Secondly, competition is a good thing but don't study keeping in mind where others are, because you will lose focus.