Yes all hens should lay eggs. There are exceptions however. The hen may be too young, too old, may be ill, may not be getting enough food and water or the right kind of food for a layer hen, may be...
If she is less than about six months, she's a pullet. When she begins laying, she's a hen. If she's older than three or so years and stopped laying, she's 'gone dry.' If she's between six months and...