Well, it's not as though that's up to you. People are not permitted to simply go and reside in whichever country they feel like. There are strict regulations in place that dictate who may and may not enter specific countries and how long those people are permitted to stay. Considering your ignorance of the world and the way things work, as well as the fact that California is on your list, I'll assume that you hold a US passport. Americans are not permitted to remain in South Korea for a period longer than 90 days on a tourist entry visa. Anyone who wishes to remain in Korea for longer than that would have to leave and then re-enter the country to set the clock back to zero, at which point the person can remain in Korea for another 90 days; however, as a tourist, you would not be permitted to rent, to open a bank account, to register a mobile phone and obviously you would not be permitted to work. So it would be impossible to remain in Korea for 90 days without an accommodation and sufficient funds, and renting hotel rooms and eating in restaurants for three months straight would be very, very expensive - we'd be talking about something like $10,000. And that's a very, very low-end estimate.
Korea doesn't take uneducated, unskilled immigrants that cannot communicate effectively in Korean and are unable to contribute to Korean society. You could look to study here, but you'd accomplish nothing but obtaining a useless Korean diploma and you would not be eligible for employment once your studies were completed.
Pick another US state or pick another country.