English Essay For Pre-ib Questions?

I am going into IB in 9th grade and I wanted to ask some questions about format and the assignment. The assignment says to:
” Read background information about World War I and write a two-page summary (typed, print size 12, double spaced).”
So I wanted to know if the background information is supposed to be about the war in general, or what caused world war 1, or weaponry.
I also wanted to know if I could write more than two pages because I have already written two and a half pages on the main cause of the war.
3) Should I add page numbers in the bottom corners?
If you want to read my essay or make suggestions here is a copy:
A Brief Background of World War I
As every Call of Duty player and soldier knows, once you pull the pin of a grenade you only have a few seconds to chuck it away from you before it blows you up. Once the fuse is lit, there is no way to stop a grenade from blowing up, and during the events that led to the start of World War I; the assassination of Archduke Franz Ferdinand lit the fuse. The events that quickly transpired afterward were inevitable, a sort of chain reaction that would later result in over the loss of over ten million soldiers, at a cost of over half a billion dollars, and with a result of some of the four of the darkest years in history.
Before the metaphorical pin was pulled, Archduke Ferdinand was in line to become the next heir to the Austro-Hungarian Empire. He planned to institute several reforms such as Trialism, where the Slavs (people who speak dialects of Slavic and share a culture) would also have a say in government where previously only the Germans and Magyars (a tribe of the Huns) had a say, but the idea of major reforms were unpopular with the ruling government.
The assassination of the Archduke, orchestrated by a Serbian terrorist group called The Black Hand, occurred when he was visiting the capitol of the Bosnia province. This province was annexed by Hungary in 1908, a move that put the relationship between Austria-Hungary and Serbia on thin ice (Serbia had also wanted to annex the land and create a new Slav state). Franz and his wife, Sophie were shot by Gavrilo Princip while riding in a car along the streets of Sarajevo (the capitol of Bosnia) on June 28, 1914. The Emperor, Franz Josef, did not attend his funeral.
Thinking that the Serbian government had something to do with the assassination, the Austria-Hungarian government sent an ultimatum to the Serbians that told them to arrest the people involved with the assassination. The Austria- Hungarians suspected that Serbia would say no, giving them reason to declare war on Serbia. In the unlikely event, that Russia, an ally to Serbia, put up more than diplomatic complaints Germany agreed to join the war. Serbia had some minor disputes with some clauses in the document which led to Austria-Hungary declaring war on July 28, 1914, and the little grenade with no pin blew up.
Instead of the war only consisting of Austria-Hungary versus Serbia, a complex system of treaties Europe had made over the previous century caused many more countries to join in the fight. A treaty between Serbia and Russia led Russia to mobilize its Army. The mobilization of the Russian army led Germany to declare war on Russia, which eventually led to over 100 countries all over the world being involved with the First World War.
The Allied Powers principal participants in the war were the United Kingdom, Siberia, Russia, Australia, Canada, India, New Zealand, Union of South Africa, and later Italy and the United States (after German submarines disrupted U.S. commercial shipping). The countries most involved with the Central Powers were Austria-Hungary, Germany, the Ottoman Empire (a dynastic state once located where Turkey is now) and Bulgaria.
While the main cause in starting World War I was the assassination of Archduke Franz Ferdinand, many political issues arose in Europe before the assassination. Many of the countries were very nationalistic, and concerned only with their own agenda instead of thinking about the whole continent. For instance, if Austria-Hungary had decided to split the annexed land with Serbia they might have avoided future conflict. The differences between the countries would have almost certainly still have led to a World War without the assassination unless major reforms in foreign policy were made in Europe. Unless the countries found a way to unify once again and be accepting and considerate of other cultures eventually another event would have set off the ticking time bomb that Europe was before World War I.