Haha, hello!
It's Jihye, native Korean, TEFL certified teacher in italki.com!
안녕하세유~~
-> 안녕하세요 is used in Seoul, but if you say 안녕하세유~~ it seems like you are from different city than Seoul. (called '사투리' =regional accent)
안녕~
사실 난 뭘 써야할지 모르겠어요 ㅋㅋㅋㅋ
잘 하셨는데요?ㅋㅋ
How did you even learn 'ㅋㅋ'?
Amazing.