First of all there are more than one verses about alcohol (intoxicant) where it has been forbidden.
Quran 5:90. O ye who believe! Intoxicants and gambling, (dedication of) stones, and (divination by) arrows, are an abomination,- of Satan's handwork: eschew such (abomination), that ye may prosper.
Quran 5:91. Satan's plan is (but) to excite enmity and hatred between you, with intoxicants and gambling, and hinder you from the remembrance of Allah, and from prayer: will ye not then abstain?
These two verse are most commonly used. Then you have another one,
Quran 2:219. They ask thee concerning wine and gambling. Say: "In them is great sin, and some profit, for men; but the sin is greater than the profit." They ask thee how much they are to spend; Say: "What is beyond your needs." Thus doth Allah Make clear to you His Signs: In order that ye may consider-
Now if someone knows Arabic then the word used in all these verses is "Khamar".
Then of course there are the verses people talk about as in your question as well,
37:45. Round will be passed to them a Cup from a clear-flowing fountain,
37:46. Crystal-white, of a taste delicious to those who drink (thereof),
37:47. Free from headiness; nor will they suffer intoxication therefrom.
First of all the word used in these verse is "Sharbin" plural of Sharab. Although Sharab is the word used in Urdu (and I believe in Persian) where it does mean an alcoholic drink. And I believe that is where few people go wrong. They try translating words from two different languages.
But without going into language implications one must read Verse 37:47 again. It clearly says that it will not be intoxicant. Scholars say that whatever drink it would be but affect will not be same as alcohol.
Then someone said Islam does not forbid alcohol but intoxic