This substack article here covers quite a lot of the current state of affairs with regard to the latest weapon that you would need to be aware of in the event of war or even just “skirmish/guerrilla” level “troubles”, namely: Drones.
Any serious conflict has now made almost all infantry obsolete if you have enough drones.
Pretty soon, it may well be which side has more murderbots to throw at the other side that wins. All the humans involved may well just become collateral damage.
Philip K Dick in one of his short stories basically had predicted an Earth where the murderbots, in all their guises, including looking like humans for some types, had essentially wiped out humanity and the story ends with one of them basically flying off to the Moon, where the last human colony exists. The murderbots can replicate themselves or build other types, so once you get one in an area… they multiply.
Add a bit of bioweapons warfare, nanobots and so on, and well… before you can hope for your AR or even sniper rifle to become useful again, you may have to wait for a really large solar flare, or the total collapse of civilisation long enough that the murderbots fall into disrepair through lack of maintenance. Of course… how you live that long, except maybe by being underground behind blast doors, Fallout style or Paranoia RPG style for those of us that are old enough to recall pen and paper roleplaying Games and the hilarious (but very murderous) Alpha Complex run by your friendly Alpha Complex Computer, is anyone’s guess.
So… along with learning terrain, map-reading and so on, you also want to learn how to hide your thermal signature (hint: An umbrella does wonders, but forget having ANY electronic devices on you at all), use your own drones and drone-making skills, and maybe, even “invent” a drone killer gun, electronics jammer and so on. Though military drones are unlikely to be stopped by anything a civilian can put together, and using such devices may well give your position away for miles.
I am not technical enough to really give you much advice beyond: Build an underground shelter you can hide in that is deep enough to survive basic bombs. And maybe do a rain-dance for hail and solar flares, as you sharpen your sword in preparation for a return to medieval times after the last automated gunpowder factories fall into disrepair.