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.