I read it before I really turned left and I know it has some lib brain but I really devoured "1914: the year that ended peace" by MacMillan. It covers all the palace intrigue in a really digestible manner despite being huge. I don't know if I have ever read a history book that juggled so many characters and events that fucking well. It shows how the institutions meant to stop war broke down, how the war as it was was utterly preventable, but in doing so shows how A war was sorta inevitable, not cause the Balkans are a powder keg but because the concert of europe was inbred and rotten at its core.

It absolutely broke me with how it described the Lost Generation's elementary school years to the start of the war. Those kids had been promised a world without war, with diseases cured in no time, a technocratic utopia, and also by those same progressives (in the technological sense) that they are not real men unless they fight in a war. The boy scouts started as an all-genders pseudo-military organization explicitly because its founder felt that boys and girls didn't have the proper survival capabilities and that they needed to learn how to hunt wild game and stich wounds and shit at the age of 10. They promised them utopia and oblivion. It fucking broke me dude.

I would suggest picking a moment you find interesting like Gallipoli or Zeebrugge, or Verdun, or Brusilov's campaigns, something specific. A lot of the war is self contained almost, and totalizing or even just broad histories of it can be disjointed. Focus on a battle or event and find the passion project someone wrote because their uncle was killed by a stray allied shell there. Personally I want to look more into the Italian Alpine campaign because my namesake, my great great uncle apparently died of mustard gas there.