This is the 3441st most frequent Korean word.
돼야
"돼야" means "must be" or "should be."
The word 돼야 is used here to indicate a condition that must be fulfilled.
시험에 합격해야 돼야 기쁘다.
I am happy only if I pass the exam.
The word 돼야 in this context expresses the necessity of a condition for an outcome.
그 프로젝트가 성공해야 돼야 우리 회사가 성장할 수 있다.
Our company can grow only if the project succeeds.
Here, 돼야 implies a condition that depends on a future possibility.