Does Islam Prohibit Smoking Or Selling Drugs? And Drinking Or Selling Alcohol?
Yes, Islam prohibit consumption and trading of alcohol and other intoxicants. it is considered as one of Al-Kaba’r (major sins which whoever commit them is to be punished either in life by the government of in the afterlife by god), the same apply to illegal drugs since it can also intoxicate the consumer. smoking is not prohibited unless you’re smoking something that result in intoxication or affect you ability to think clearly. (if that’s the case it also considered one of Al-Kaba’r), however, even smoking normal cigarettes is considered by many Islamic scholars to be a sin (smaller one) since it harms the body and increase chances of dangerous diseases, but it is not prohibited or banned in Islam.
keep in mind that the consumption of any intoxicants even in small not harmful or intoxicating amount is still considered prohibited as will be mentioned in Hadith #1865.
I will mention some verses of Quran and other texts from Hadith regarding alcohol and intoxicants.
In Quran, Surah Al-Ma’idah, verses 5:90 and 5:91:
“(5:90) O you who have believed, indeed, intoxicants, gambling, [sacrificing on] stone alters [to other than Allah ], and divining arrows are but defilement from the work of Satan, so avoid it that you may be successful.
(5:91) Satan only wants to cause between you animosity and hatred through intoxicants and gambling and to avert you from the remembrance of Allah and from prayer. So will you not desist?”
In Jami’ At-Tirmidhi, Hadith# 1865:
Narrated Jabir bin ‘Abdullah :
That the Messenger of Allah (Peace be upon him) said: “Whatever a lot of it intoxicates, a little of it is unlawful.”
 Surah Al-Ma’idah [5:90]
 Jami` at-Tirmidhi Book Number 24 Hadith Number 1865