welcome to the forum nightriders_leo

Well the most important book that you need for your GMAT prep is the Official Guide (also referred to as OG). This book is written by the makers of GMAT and is a compilation of past GMAT questions. The 12th edition is coming out on 23 March so it'll be better if you wait and get the latest one.

https://www.amazon.com/Official-Guide-GM ... 958&sr=8-1

In addition to the OG, you also have the the verbal review and quantitative review also published by GMAC and are excellent additional resources to the OG.

For sentence correction, you can use the Manhattan GMAT SC guide 3rd edition. This book is truly a SC bible and has some fantastic explanations and techniques to deal with the SC questions in the exam.
In addition to MGMAT SC guide I'd advice you to go through a grammar book (Wren and Martin or Doing Grammar) to improve your grammar basics.
Note the MGMAT books are not available in UAE so you will have to buy them online, either from their website (www.manhattangmat.com) or on amazon.
Also when you buy any Manhattan book you get access to their 6 CAT (online exams).

For the Critical Reasoning section, I'd reccomend the Powerscore GMAT CR Bible. As the name suggests, this book is truly a bible for the critical reasoning section. They have explained each type of CR question in a detail manner.

For the Reading Comprehension, I found the OG and the verbal review best for this section. As for tips to improve in this section, Beat The GMAT has a collection of fantastic tips from GMAT experts such as Ron Purewal and Stacey Koprince, to name a few on how to attack this section.

As a piece of advice I'd recommend you to get your basics straight before you do the OG questions. You will understand the questions and their explanations better.

For a complete list of GMAT resources available you can refer to the following site: https://www.beatthegmat.com/resources.html
This is an extremely helpful link. You can find some extra notes and flashcards from previous GMATers.

Also as an extra tip: Search for posts made by GMAT experts such as Stacey, Ron, Stuart Kovinsky and Ian Stewart. They have some brilliant tips and shortcuts to deal with various types of questions. A must if you want to score well in your GMAT.
And lastly, you have 1000s of questions on this forum to practice from, with questions having varying difficulty levels. So this forum provides a huge list of questions to practice from which when combined with the above mentioned resources should be sufficient practice for any GMATer.

Practice Tests

You can download the 2 free GMAT Prep tests from the website www.mba.com . These tests are the closest things to the actual exam, in terms of format and level of difficulty. Try to take these tests atleast 2 times before you take the actual GMAT. Again a must.

For more information on other practice tests available check out the following poll: https://www.beatthegmat.com/best-practic ... t1327.html

Well I think I have covered mostly everything you would be needing for your prep.

Also you can read the debriefs of various members who have taken the GMAT and get an idea of how you want to approach your studies. Plus they tend to motivate you to study for the exam with full enthusiasm
Some very helpful debriefs are those of Eric (founder of BTG), mayonnai5e, ngufo, logitech, adham (the last 3 are must read debriefs for non-native english speakers)

So good luck with your prep and wish you success for the exam.