If it is possible please tell me that for what Surah Ar-Rahman is. I asked many people but they send me it Tarjuma. But still I couldn't get it as for example Surah (Waqaha) people say that if you read this Surah after Maghrib prayer you will be never poor. So, my question is that I have a problem so someone told me to read Surah Ar-Rahman. When I asked him tell me the benefit he can't say as I told you Surah Waqaha it is for Risq so for what is Surah Ar-Rahman hope you can get what I want to say and hope you answer me.

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.

The excellence that results from reading chapter 55 [Ar-Rahmaan] is that whoever reads a letter from it will get a reward and every reward is multiplied tenfold. This excellence is not peculiar to chapter 55, but this applies to all chapters of the Quran. The Prophet said: "Whoever reads a letter from the book of Allaah will get a reward, and the reward is multiplied tenfold. I do not mean 'Alif Laam Meem' is one letter but 'Alif' is a letter, 'Laam' is a letter, and 'Meem' is a letter." [At-Tirmithi]

We do not know any authentic narration about the excellence of chapter 55, however, there is a narration about the excellence of this chapter that is classified as weak by the scholars. The narration is the following: "Everything has a bride and the bride of the Quran is chapter 55."  Al-Albaani said that this narration is Munkar, [objectionable] which is kind of weak narrations.

Finally, it should be noted that the narrators of the narrations reported about the excellence of chapter 56 which state that whoever reads it will not be poor, are weak. So, a Muslim should read the Quran seeking the Pleasure of Allaah and seeking a reward from Him by reading it. 

Allaah Knows best.