Is there a timeline somewhere keeping track of all the events? Specifically I am trying to figure out when the Awakening DLC for Halo Wars 2 takes place
Halopedia has a page dedicated for the timeline of when the events take place. You could look there.
I’d suggest taking a look on Halopedia first as it is probably there like covenantslayer pointed out , but in the case you cant find it there I’d recommend searching around online for it ( There are a ton of Halo timeline/lore videos on Youtube in the case you still cant find it )
Absolutely, with how expansive the Halo story is, go for the right sources. FYI Anubis316, Halo Wars 2: Awakening the nightmare happens two months after the five day first battle the UNSC forces contingent to the UNSC Spirit of Fire led by Capt. Cutter did with Atriox and his Banished forces on the Ark. By then, neither side could gain purchase and overtake the other, Capt. Cutter and the UNSC forces under his command almost completely destroyed all of Atriox’s operations and probably defeated half of his troops and stranded the other half after the UNSC destroyed their access to the Ark’s portal network. Just in case you didn’t know.
As said above, Halopedia has all the answers you need. If you want a visually pleasing cliffnotes version, then I’d recommend picking up a copy of Halo: Mythos.