I can only live to be 23. Am I a short-lived ghost?

23 years old is really not big for the span of life now. But I don't know what you're talking about, whether the doctor said you were ill or you went to a fortune teller and the fortune teller told you. If it is because of illness, keep an optimistic attitude and cooperate with the doctor. Now that medical technology is so developed, there must be a miracle. If you are a fortune teller, don't believe it.