What is the number one thing a person must do if they have COPD?

What is the most critical action an individual with COPD should undertake to manage their condition effectively? Is it adhering to a strict medication schedule, engaging in regular pulmonary rehabilitation, avoiding exposure to triggers that exacerbate symptoms, or maintaining a healthy lifestyle through diet and exercise? Understanding the priority step can significantly impact the quality of life and overall health outcomes for those living with COPD.