Need help finding a book (fiction)

I only read the synopsis and the wiki page of the author. This was a while ago.

It follows a man, former military. I believe it was set in a timeline where America had either split or was generally not the same America we know. I remember comparisons to Jack Carr works, even some Punisher comparisons. He crossed the US, I don’t remember what his objective was. But he had interactions with young men, 18-25 or so where he was confused about their vernacular and commented on it. That scene, I believe, was somewhere around Oklahoma.

It was a bleak outlook on the future, not quite apocalyptic but sort of an every man for himself type situation.

It was definitely a series. I don’t know if it is good or not, but it piqued my interest.

Thanks in advance.