Ask Lemmy

Dried bean mixes and rice can be kept in sealed containers in a cold, dark place for upwards of 5+ years. They are super cheap to buy in bulk. It's about as close to nutritionally complete as you can get, and only requires boiling water to cook. Dried beans also frequently can be rewetted and sprouted, at least for the first couple years.
Gardening is nice but fresh veggies don't keep through the dark of winter.

I am especially fond of the soup mixes that North Bay Trading sells. It's about 4-7$ a pound depending on how much you buy, but it keeps for basically forever, and each pound of beans makes multiple gallons of awesome tasting soup. Sautee up your meat of choice and add it in, it's great and will not leave you depressed.

With a few acres at your disposal, you have a lot more options. This is drifting out of bulk item territory but it counts.

Learn how to can and get the bulk supplies necessary for it- it doesn't take much at all to get started. If you are going to have to start living off the land more, canning is critical to surviving winter without suffering from malnutrition. Plus, canned goods are a highly prized barter item.

Get chickens. Chickens are easy to keep, need little space, can be allowed to free-roam around your few acres, and are a great natural pest control. They auto fertilize and aerate your garden, eggs are nutritionally dense for you and can be sold, and chicken meat is a solid protein source. They grow to maturity extremely fast (<6mo) so can produce very quickly from even a small originating flock.

Tools and mechanical knowledge are key. When push comes to shove in rural areas you are going to need to fix all of your own stuff to keep things like electricity, fresh water, heating, your road vehicle, and your farm implements all running. You can outfit yourself with some pretty damn good hand tools at harbor freight for <$150 that will be enough to disassemble an engine, stove, or other house appliance if needed. Start watching youtube videos on basic vehicle/tractor and house appliance maintenance, take notes. Find repair manuals for stuff you own, and buy paper copies of them.

Start collecting spare parts like fuses, electrical wire, common replacement parts for around the house stuff, tractor and car consumables like spark plugs, oil, etc. You don't realize how dependent you are on the modern industrial supply chain until it is abruptly cut off, and everything around you just stops working in less than 6 months. This won't last forever of course, but it will least extend the period you can operate normally.

If you have a groundwater well pump on the property and not a public water utility, find an alternative way to get water out of it. Clean water is the key to all life, if you can keep water flowing, you can make everything else work. Grid power can disappear at any time and may or may not ever be restored, so an electric well pump may not be useful. Have someone outfit the well head with a manual hand pump if the well is shallow enough to support it, or have a way to power or replace the electric well pump with a generator or car power.