I was reading NEET Recieves a gaming sim, and liked how he used a save/load ability to use in combat to predict opponent's moves and I was wondering is there was a novel with a similar ability that used it for military warfare. It can be modern warfare but would prefer something along the lines of I am the Monarch or Reincarnated Lord. If you have suggestions for anything like this or a novel with a military leader that can accurately predict enemy enemy strategy I'd love to find some more. Reading list is up for comparison, most likely novels would be in the 'Game' or 'Redo Stories' list.
A similar novel (it's a novel, right?) is All You Need Is Kill. It's a time loop, but it has what you're looking for.
Absolute Choice and Master Hunter K are the only novels i've read with anything close to a proper event repeat of some sort that isn't just/only reliving the past _____ years or existing in a game they've already played/beaten knowing what ought to happen and dealin with it. those aren't really at the sort of scale you're looking for, though. at least not that i've seen.
Tensei Shitara Slime Datta Ken / Reincarnated into a Werewolf, the Demon Lord Servants : military / leadership novels
I stopped reading right after to stockpile chapters but Single Player Only supposedly introduced a save/load though it seems limited since it was just introduced from last I read
Re:Zero Kara Hajimeru Isekai Seikatsu technically since he return to the last savepoint after he dies
What you want is like wanting a hentai without sex .-. Just give up. You can find a lot of game element novels but most of them are VR or real world and there is no save/load in them.