There is no single American flag. Each country in America, both north and south, has its own flag.
Some have stars others do not.
Should you be referring to the US flag then there are 50 stars presently.
There are 50 stars on the current flag of the United States of America - one star for each state in the U.S.A. While "America" is commonly thought to describe the United States of America it is technically inaccurate. The American continent includes North America, Central America, and South America. Each of these Americas include a number of countries. For example North America includes Canada, the United States, and Mexico. Each country on the American continent has a different national flag.