Hello Abdullah:
All the information you require is available on this site. If you need to pass the test now that is up to you but my suggestion is that you wait about a month before applying for the citizenship and then take the test.
In the mean time spend some time here and read all three chapters and start doing the quizes. If your understanding of English is average then you will be able to prepare for the test in less the 20 hours. 4 hours for each chapter per day and then 8 hours for complete review and all the quizes. you can reduce that time if you have better understanding. In FIVE days
Again don't be in a hurry to just take the test as it cost £34 and pretty expensive.