Simplify the following text for a Grade 9 native English-speaking person.
Original: The Royal Antigua and Barbuda Defense Force has 285 members ; within it , 200 12-to-18-year-old youngsters make up the Antigua and Barbuda Cadet Corps .
Simplified: Antigua and Barbuda is an island nation located in the eastern Caribbean Sea on the boundary with the Atlantic Ocean . Antigua and Barbuda are part of the Lesser Antilles archipelago .