안돼: Korean word meaning "no way," usually used in moments of disbelief, shock, fear, or defiance. 아니오: No.

andwae has meaning of "don't" "must not" "should not". ahnyo is used when you answer to question, meaning "no".

안돼/요 'andwae/yo' is more similar to the word 'can't in english' ex: 감기 걸리면 안돼요 you can't catch a cold it has a connotation of not wanting something to happen almost 아니/요 'ani/yo' is just like no in english ex: 한국말 잘해효? Are you good at Korean? 아니요, 한국말은 잘 못해요. No, I'm not very good at Korean.