The drink that Koreans drink the most, is Soju.
If you go to Korea, you can drink the cheapest and easily.
It is Soju.
Soju is a place where Koreans meet with their friends in the evening and eat a lot with pork belly.
Usually in restaurants, the price is around 4,000~5,000 won.
Soju (/ˈsoʊdʒuː/; from Korean: 소주; 燒酒 [so.dʑu]) is a clear, colorless distilled beverage of Korean origin.
It is usually consumed neat, and its alcohol content varies from about 16.8% to 53% alcohol by volume (ABV).
Most brands of soju are made in South Korea. While it is traditionally made from rice, wheat, or barley, modern producers often replace rice with other starches such as potatoes, sweet potatoes, or tapioca.
If you want to drink Soju, if you do not know Korean, simply say this.
Juseyo! Soju! (Please, Soju)