To improve your endurance for daily activities like climbing stairs or walking long distances, start by gradually increasing your physical activity level through consistent aerobic exercises such as brisk walking, cycling, or swimming. Aim for at least 30 minutes most days of the week. Incorporate strength training exercises for your legs and core to support better stamina. Stay hydrated, maintain a balanced diet rich in whole grains, lean proteins, and vegetables, and ensure you get enough rest and sleep. Over time, your cardiovascular fitness and muscular endurance will improve, making everyday tasks easier and less tiring.