Hi! That’s a great question.
One Chinese word I really like is 加油 (jiāyóu). Literally it means “add oil,” but it’s used to encourage someone, like saying “keep going,” “you can do it,” or “good luck.”
I like it because it’s such a positive expression and people use it in so many situations, exams, sports, work, or even when a friend is having a hard time. It’s a simple word, but it carries a lot of encouragement.