Hello Vivek,

It is true that NCERTs works the best for NEET. Learning up all the chapters will definitely help you build your basics.

For more practice and in-depth knowledge you can surely take on M.S. Chuauhan for Organic Chemistry. This book has a perfect balance between theory and questions.

And yes, topics from organic chemistry of both the classes are included in the same book.

MS Chauhan meet books contain both class 11th and 12th portion but you need to purchase the complete set of the publication so that you could cover the entire portion cause it is subdivided as book is prepared specially for meet then you may find topic expanded and divided as compared to 11th and 12th portion.