JEE Main Preparation

Taking one extra year generally does no good. If you have any chance in KIIT, then go for it. Never try to look back. If you wait one extra year to pursue JEE, you will be bored and most probably start hating studies. Just go ahead but be amongst the best.
All the best.

You should read ncert sllaybus and take admission in any famous coaching center

You should read ncert sllaybus

You can join any coaching institute with the best faculty.

there us no reason that is if u go for preparation there teach u start with basic

NCERT first, Then BS Grewal for Maths, HC verma for physics, NCERTand Pradeep (if you like Like too little in a big package) Arihant books are also good but they are not targeted. (11th course is more important as you tend to forget)
And lots and lots of Practice papers. Are suffice to get a good rank. Best of Luck!

Deoends uoon which city you reside in. In Delhi, Vidyamandir classroom course is considered best.

Hi Santosh,
Jee mains has already been conducted. The Offline exam was held on April 3, while, the Online exam was held on April 9 and 10, 2016 respectively. For JEE Advanced, kindly refer the below link :
https://www.shiksha.com/jee-advanced-important-dates-exampage
For coaching related issues, kindly refer the below link:
http://goo.gl/989ows
I hope this information helps. Please feel free to revert.
All the best.

Be thorough with NCERT books. Clear your concepts at every point. Understand every topic to depth so that you can answer any question on it. Practice previous year questions. You also have to score good in boards. Be focused and meticulous. You can join a coaching for right guidance. All the best.

you should join Allen or Akash