You can get a health certificate in the afternoon, anytime, as long as it's not at night, but you must combine work and rest, don't work too hard, have a good mood during this time, and have a blood test to see if there is any problem with blood routine, sleep well, and don't eat some spicy and irritating indigestible food.
However, you are required not to eat in the morning and noon, because you have to draw blood on an empty stomach to apply for a health certificate. Blood test items include liver function transaminase. If you drink water or eat, the accuracy of the value will be affected. At the same time, three days before the physical examination, you should also have a light diet, do not drink, smoke or eat greasy food to ensure adequate sleep. Women should also avoid menstrual period, so as not to affect the accuracy of urine routine. You also need a chest X-ray and an electrocardiogram to get a health certificate.