The drinking and smoking age is 18 years old. When younger, its not a crime if you smoke or drink but it is a crime to sell alcohol or cigarettes to minors. You must pay a big fine for this or your store may be shut down for some time.

Being in possession of small quantities of drugs will be subject to fines and/or alternative penalties such as community service or possibly deportation.  However, a foreigner could be deported or sent to jail depending on the situation.  If you are caught trying to take drugs in or out of the country, the penalties are more severe.