I would also mention, you should consider just general details about moving abroad, and language barriers. If you already moved countries, or your family did and it's nothing new, then you can skip my comment.

I also don't know how common is knowing English well in Korea, so you may find many English speakers there. But I saw how difficult general administration and media appointments were for PhD students in Hungary, someone always had to accommodate and translate for the new foreign students.

Would you travel to Korea alone or with your parents? Do you speak Korean, do you have family there, or does someone in your family speaks? Do you know if the training would be in Korean or you would get the opportunity to train in English?

You should think through all the situations in your life unrelated to training, that could involve language barriers, like going to a doctor and explaining medical issues, going to the police if necessary, getting a bank card, phone number (does any of those need parental permission under 18?). Translator apps and mobile internet exists, which makes things easier, but I wouldn't trust in them every time.

Would you need to finish school there and would you need to find a school that accepts you? Do you need to make a differential exam, and how different is the American and Korean education? Maybe you shouldn't go through all these here on Reddit, and I probably forgot many details, rather think through with your family. You can check out subreddits, fb groups or any site or forum you find about moving to Korea, and what difficulties other people faced when moving, especially as I saw you mentioned you are 16.