Bryant Poss

Intriguing Premise

Placing the character in such a predicament in the beginning is a good choice as it provides ambiguity and suspense for the reader regarding he protagonist's situation. It also affords you the opportunity to begin developing your character. The plot is interesting, and you do well with the change of scenery with the dream or hallucination segment. This beginning will allow you to play catch up with the protagonist's abilities, which is always fun.
Your primary issue you deal with is over description. I'm a big believer in less is more. Let the actions responses of the characters help draw the picture for the reader. There's no need to verbalize every detail. I know that's how you see it in your head, but place yourself in the reader's shoes. Would this action be implied through dialogue or some other reaction without the description? Here are some points I saw, and if I read something wrong, I apologize. I have been an English teacher forever, so certain things just stick out to me.

Leaning backwards, he rested the backs of this thighs across along the upper edge of his desk... (This sentence comes across as somewhat awkward. The “being of average height” part seems unnecessary. You might want to consider rewording it. You may want to consider a simple, clucking his tongue, in the sentence before that one.)

Secrets others couldn’t here, but she could. (Change to hear)

Fondly, he looked down at the music box. (You begin many sentences with an adverb then a comma, which is fine. It helps break up the problem of always beginning with a pronoun. You may want to mix it up with something like. A fondness pulled his eyes to the box.)

It was the music box she turned. (It was the music box to which she turned)

Raged outlined across her young features (either rage outlined her features or her features outlined with rage)

Dogs not that smart (Dog’s not that smart)

Mom is going to kill you. (Just italicize the word rather than explain emphasis)

Arthur? what in the-... Arthur? What in the—

(You can use an em dash in some of the places you use an ellipsis.)

These are some things that I saw, and believe me when I tell you that this is stuff you correct with time and practice. Overall, I think you've done a very good job.

Love a Good Historical Fiction

I enjoyed the first chapter. It introduces the protagonist well and the situation he is in. Writing in first person makes it easier to develop, but it is trickier to develop those around him except through action, but that's best anyway. You do well to keep the reader in the scene and hep understand what is going on. This is a good period, as WWII usually gets most of the attention. Here are some notes I made while reading. I certainly hope you keep it up.

Prologue
It is, according to the Julian calendar, on October 23, 1918, the “Great War” as it was known at that time began to end, a war to end all wars, and another started; a revolution that would eventually shape the geopolitical landscape of the twentieth century like no other. (The beginning of this sentence is confusing, and the subject/verb agreement is blurred. October 23, 1918 of the Julian calendar was the beginning of the end for what would be called the Great War, the war to end all wars, but it was also the beginning of a revolution that would shape the landscape of a nation and with it the world.)

Involve the civilian population however (population; however,)

There were no fewer than 150 national participants

Burkhard Huber, or Buck as his friends would call him,

Chapter 1
(As round after round of artillery) maybe instead of as artillery round after artillery round
turn west here,”

adrenaline-induced hand

“Yes, they are located about here.” I pointed again. (no need to say I said when you immediately follow with I pointed)

And hit it off immediately doesn’t sound like the voice of the narrator. Maybe we found ourselves on common ground.

An issue with writing in any person, be it first or third, is beginning too many sentences with a pronoun. I think, I saw, I raised . . . There are few things more attractive than a complex sentence beginning with a dependent clause. I used a small, waterproof match so I could see to examine the distance to the artillery placements. (Using a waterproof match, I could examine the distance to the artillery placements.)

Keep up the good work. It's always rewarding doing all that research for these types of novels.

Good Control of Voice

If this is the beginning for your writing, you've done an excellent job. Giving the narrator such a unique place to start (a week before the end) creates an umbrella over what I assume will be the flashbacks to come. The voice of the narrator maintains a consistent tone, and the vocabulary matches the carefree attitude of this narrator. I've just begun reading on here, and I come across quite a bit I can't really get into, but this kept me going.
The only thing I'd watch out for is using the same word in different context so close together like endlessly trying and end. Maybe try exhaustively trying since end comes so closely after. Other than that, I can see you edited carefully and removed the inevitable typos, and I appreciate that. Good job.