That's okay! I'll give you as much info as possible.
Panem:
The nation of Panem was established during an unknown time period following the destruction of modern civilization. It is situated primarily on the western side of North America, and the Capitol is located in an area formerly known as the Rocky Mountains.
Panem is run by a single-party dictatorship that appears to be led by President Snow. It appears to be the dominant society in North America, and no other nations or civilized societies beyond Panem have been mentioned, so it is unknown if any exist at all.
The Games:
The Hunger Games are played each year in the country of Panem. They are not actually a game, but rather a fight to the death between 24 children (called tributes) between the ages of twelve and eighteen. One boy and one girl from each of the 12 districts are forced to participate in this event in a large, outdoor arena. The event is televised to the people of Panem, and the last living tribute is declared the winner.
The Capitol:
The Capitol of Panem is where the wealthy and powerful people of the nation live. Not only are the Games controlled from this point, but so are the twelve districts. The Capitol is a dictatorship, seemingly run by President Snow. It is also the only mentioned major city. It is thought to be located in the northwestern section of the United States of America, seemingly in the Rocky Mountains.
The Districts:
The nation of Panem is separated into a total of thirteen nation-states known as districts, twelve of which are recognized as operational by the Capitol, and each being solely responsible for producing, procuring, or refining goods in a particular industry as dictated by the Capitol. All of the districts are subject to the unrelenting will of the authoritarian Capitol, and have no known influence concerning the national politics of Panem beyond their own individual territories.
The districts barely interact with each other, so each district generally has a unique culture unaffected by the other districts which strongly influenced by the goods it produces. Welfare levels vary significantly, and are often dependent on the goods it produces; some districts, such as 11 and 12, are far more impoverished than wealthier districts like 1,2, and 4, though apparently no district is nearly as wealthy as the Capitol itself.
Originally, there were thirteen districts in Panem. During the Dark Days, the 13th district was obliterated by the Capitol and is no longer recognized as operational. Each District provides something different to the Capitol; for example, District 12 provides coal and District 4 provides fishing.
Got the info from the wiki. I think that covers all the major points. If you have any most questions, just ask!