I've done some more copyediting, tried to fix the grammar issues and reduce the extent of quotations. If you have any objections, please tell me though I think it's alright for a good article now so I'm going to promote it and good work on the research you did for this article. Tayi ArajakateTalk15:51, 7 January 2022 (UTC)[reply]
"It focuses on his birth to the Malayalam composer R. K. Shekhar and his wife Kasturi in Madras (present-day Chennai) on 6 January 1967" I have a question regarding this, does the book focus on his birth itself? That doesn't sound right, I assume it's meant to say it begins with his birth. The date of birth (and even his parent's names) seems unnecessary for such a short summary and for the lead as well.
"The book also chronicles on his cinematic debut ..." should be "The book chronicles his cinematic debut ..." In general, the summary needs better comprehension.
"Rahman believed most information in the book had been said himself in the media interviews ..." doesn't make sense. I'd suggest rewording the entire sentence.
"She recounted the process was slow..." should be "that the process".
"... was not on his mood to talking..." should use "for" and not "to".
"...Kabir likened working with him with doing an adventure..." is grammatically incorrect, it should be something like "...Kabir likened working with him to being on an adventure..."
"...observed of the book..." is grammatically incorrect.
Lots of other little grammatical errors, weird sentence formation and general comprehension issues like the ones listed above, I'm not going to list all of them but please do correct them. In addition, relying less on quotation and more on summarisations may be more useful in conveying information from the sources. Replacing some of the repeated "said(s)" in the article with something like "stated", "according to", etc would also improve flow. The comprehension is the only major issue with the article at present.
"Critics were polarised in their reviews, receiving positively its question-and-answer format while panning Kabir's effort in collecting information of Rahman's Tamil songs." This line should be removed as it's analysing the reviews without a source, i.e it's synthesis. I would instead suggest providing broader summaries of the individual reviews.
The first line in the lead should describe it as a "biographical book" rather than just "biography" to avoid any ambiguity as the author is described as a documentary filmmaker as well.