How to solve the problems of drinking boiled water and texting on mobile phones when traveling to South Korea?

Hello, I am an international student in Korea. Drinking fountains in Korea can be said to be everywhere. If you really can't find them. You can drink boiled water in any store. South Korea's drinking fountains are connected to cold water (South Korea's drinking fountains have refrigeration function, and the water is really cold). You don't have to press the button, but hot water can only be connected by pressing the button (mainly to prevent children from being burned). As for the mobile phone, you may not need it when you come. If you want to stay in Korea for more than a week, I suggest you rent a mobile phone from a communication company. Smartphones are very useful. Sending text messages may not work. In Korea, only Korean input is supported. You can use QQ to open videos. South Korea has a large mobile phone traffic and a fast 4G network. However, you should be careful not to trust China people here, because in South Korea, China people often cheat China people. If you know nothing, you can leave me a message. I hope you have a good time in Korea.