Santosh Kumar

Assess yourself. Start with a book read one chapter and solve end of chapter problems. If you are able to do this for most of subjects, you do not need tuitions . If you are stuck and cannot make progress then it is a good idea to get help. Remember you can only decide if you are making progress. You would feel confident and your score on tests at schools would be a good indicator of your progress.

If you are able to get started and get hang of things then obviously it is not required. Read through the book. Does it make sense? Can you work out end of chapter problems and exercises yourself. Can you ask right questions? Can you get help from teachers at school? If you are able to progress then good. However if you find yourself repeatedly getting stuck it is good idea to get help with tutor. However I agree most of stuff is basic and most students should be able to do it.

Only you can assess it.  Essentially the syllabus is same. The concepts would be explored in a more elaborate manner at IIT JEE coaching. Most students are not able to manage time to cover it all. Lot of time is wasted in traveling, settling down for classes, repeating same topics and worrying about future. If you are still struggling with basics, consider getting one to one help with a dedicated tutor. Once you cover basics, you can go far coaching classes.