The ideal is at minimum one week because first of all it's the threes rule. Rule of threes is you can survive up to three minutes without air, three hours without shelter (depending on conditions iirc), three days without water, and three weeks without food. You can survive a week on nothing but water. I've done it before, mostly. Your main problem is just not having the energy to say flee when you really need to, and also the beginning of real starvation and nutrient deficiency can fuck with your head and cause you to make bad judgments. Also it's beccause by and large three days is not a real emergency, and you'll solely have that small stockpile to take stock of the situation itself and not have foraging for food while exposed to danger sapping your precious 72 hours of planning your next move, but in truth it won't get you anywhere at all. This is especially true because you should plan on potentially having the power cut or water supplies disrupted which brings me to your list:
~eggs, meats, cheeses,
Like what the fuck kind of a list even is this? Lad, you better not be stockpiling that unless you're planning on storing the stuff like an admiral would on his galleon speaking of which I found an awesome channel I kept wanting to post here but didn't out of a general ban on chanpostinghttps://www.youtube.com/watch?v=2FpEEb44suM
Really great channel although I get weird vibes from that guy and his relationship to the youth but anyway, cool channel, super EC tier.
As to your list, I'd pretty much strike off dairy entirly unless it's cheeses and cured meets which you can leave in a broom closet for the next year or three. If you don't have jerky and summer sausages or canned meats then just don't even bother, because unless you live in cold climes that shit is going to cost you a lot of money and it is going to go bad. Eggs can keep surprisingly well however most storebought eggs are machine washed after laid by malnourished factory farmed hens which means that they're not going to keep so well as farmer's eggs, and even if they did, you're already buying it old anyway, which means spoilage even while refrigerated.
Basically, it's a cans of beans and rice world, which itself won't get you far weird I'm getting super deja vu. Did we already have this part happen? Where I talked to a Finnish guy about prepping in the winter because Russia did Russian things? 2014?
Anyway, forget everything about that list. What you're going to need is tools, preferably survival tools, some basic gardening implements, a space to do a small grow operation if able, fishing poles and hooks+spare wire and lures, trap setting materials, and plenty of water decontamination and collection supplies. While I do think like most games it's way overly simplistic, This War of Mine is unironically one of the best survival sims out there, especially because odds are you're not going to be some badass from some detached from reality Hollywood movie, just a regular person, and that does mean keeping spirits up and finding things to keep busy and maintain social cohesion is key. You may think it's all going to be fine and dandy because you've never even had the power out for two days before, and meanwhile by day three your whole family is at each other's throats.
People are your biggest problem ultimately. Which means banding together into survival communities, maintain as best ties you can with select neighbours, don't start shit with people you haven't got to, and maintain a sense of purpose and morale in your troupe. Actually World War Z by Max Brooks did a fantastic job about this, I think, especially in that it blew apart social expectations from ground reality which was possibly most vivid in its depiction of all these suburban idiots fleeing north to Canada and promptly starving and freezing to death.
Forget any of your devices that require batteries, they're soon rendered useless. Maintain a rechargable flashlight and radio, the kinds with handcranks and shaker flashlights, as well as stuff like paracord and good camping supplies which you may need if you cannot shelter in place.
However all that being stated, do know which scenarios and timelines you're at least marginally prepared for, and which lengths you are not, including most importantly an understanding of how long you can expect and be prepared for that+1. So to say, power goes down for only a week, be able to get by on two weeks of supplies. Also be able to pack your B.O.B. smartly, such as say for an example in event of nuclear exchange or war, or some calamity where you can't expect power to come back on or surviving comm towers rebuilt in the next couple months bringing your cellphone is completely useless, but it's a literal life saver if you're only planning to have a shorter scenario where you can find a working power outlet and need to radio somewhere for help with a cellphone.
Know your situation. Don't pick survival guy for the middle of a desert when you live by an icy stream, and don't pack for a full year when it should be over in two weeks; don't dress yourself for surviving a pandemic in a radiological attack, or prep just for war when a solar mass ejection takes everything electrical offline. I think that it was nice of The Division, unrealistic though it may be, to also touch on a couple of these survival issues. You need more than just good nutrition and clean water to survive, and in most scenarios where you'll actually need it you can probably kiss a bunch of those comforts goodbye. As we've seen with this pandemic though, even in a light scenario where shit still mostly works, you shouldn't expect complex logistical networks to come back online in any appreciable length of time, meaning you shouldn't prepare for anything the govt authorities say about overly cheerful things that are exclusively designed to prevent a mass panic. However all that said you should also plan for a cascading event failure, of such as say a four horseman scenario of say the 20s variety, which is to say that just because it is a mass famine doesn't mean it could not also morph into becoming both a war problem as well as a biological contaminant problem, and yes chemical, biological, and radiological weapons do require different types of PPE however you should absolutely have a p100 mask at the ready in your survival kit alongside your water filtration and firearms or whatever, which brings me to the last problem: avoid conflict, but be ready for it.