First of all, according to your parents' physical fitness and perseverance (whether they are willing to stick to it or not), check the body fat content, and you can start fitness at around 20%. According to their time and body, recommend different equipment (preferably go to the gym). At first, we suggested low-intensity exercise, running first, anaerobic stretching, and then we can do something else. For example, use a set of dumbbells ... more than one set a day, with a break of two or three minutes. When you feel better in the future, you can increase your training intensity. Give parents more high-protein foods, such as fish, meat, eggs, milk, etc., to promote muscle formation. If they want, they can also add some protein powder.