When a person lives to 100 years old, 120 years old, he is healthy and not sick, then he can continue to live, right?

Yes, it's a natural law, because as long as there is nothing wrong with you and your body is not sick, people can live healthily. So still. As long as there is nothing wrong with the body, you can live healthily. No matter how old you are, as long as you have a healthy body, it is possible to live to any age.