How do you say this in Korean? good morning, good evening, good night?

(Good morning):
Literally: 좋은 아침 but "안녕" Or 잘 잤어? 잘 잤니?(Meaning : Did you have a good night's sleep? or Did you sleep well?) (informal / casual)

Literally: 좋은 아침이에요 / 입니다 but "안녕하세요" Or 잘 잤어요? 요 is informal but polite Or 안녕히 주무셨어요? more formal(polite)(Meaning : Did you have a good night's sleep? or Did you sleep well?) (formal / polite)

굿모닝 - Konglish "good morning"

(Good morning, afternoon, evening):
안녕하세요

(Good night):
굿밤, 굳밤, 굿나잇 (Slang & Texting, informal / casual)
잘 자 (informal / casual)
잘 자요 (informal polite)
안녕히 주무세요 (more formal) polite