At first in 1914 the Government launched a mssive campaing to persuade young men to join. The country was swept up in a wave of patriotism, anti-German feeling, and adoration for the militar and The government's campaign was initially very succesful, with half a million men joining up each month for the first 5 months of the war. The age limit was 19, but boys younger got through by simply lying, there were no stringent age checks.
The youngest soldier to die in WWI was 15. There was definitely training, but it was only a few weeks, not the months that modern soldiers get (they simply didn't have enough time to spend months traning the new recruits) However, by 1916, it was clear that more soldiers were needed. In January 1916 Conscription was introduced, whereby every unmarried man between 19 and 40 had to sign up the military.
In may this was extended to married men. The only men who were not forced to join were those workng in 'essential industries' such as Weapons production, ... more.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.