Chapati is written down as food so,

1. The first step is done by the teeth to crush it into smaller pieces.
2. Then the saliva has salivary amylase enzymes which breaks down the starch in the food to give sugar and it also wets the food to make the passage of food down the alimentary canal easier Peristaltic movement occurs all along the gut till the food reaches the stomach.
3. In the stomach the digestive functions are taken care by the gastric glands present in the walls of the stomach, the gastric glands secrete hydrochloric acid an enzyme called pepsin and mucus.
4. And then the food reaches the small intestine longest part of thealimentary canal, the small intestine recieves the secretions of the liver and pancreas which help in the digestion of food , the juice secreted by the liver is called bile juice and the juice secreted by the pancreas is called pancreatic juice.

​​​​​​​In the inner lining of the small intestine there are finger like projections called the villi which absorb the digested food and the remaining undigested food that enters the large intestine it absorbs water from it, the villi are present here also.
Thus, the digestion of chapati is completed. The diagram is given below: ​​​​​​​