The undisputed experts when it comes to key survival gear? The rangers who save hikers who go astray. Jeff Webb, a search-and-rescue ranger at Yosemite National Park, has worked on more than 200 rescue missions. He's also seen action in Big Bend, Yellowstone, Canyonlands, Joshua Tree, and Rocky Mountain National Parks. With his advice, our editors put together this ultimate survival kit for hikers.
For global catastrophic risks the costs of food storage become impractical for most of the population  and for some such catastrophes conventional agriculture would not function due to the loss of a large fraction of sunlight (e.g. during nuclear winter or a supervolcano). In such situations, alternative food is necessary, which is converting natural gas and wood fiber to human edible food.
I’ll take a person with common sense over one who has a lot of survival knowledge and skills. There is too much emphasis out there on wilderness survival. That will be a rarely needed skill set. More common will be urban survival, and suburban survival. Age and physical condition will have more to do with being able to survive a long-term disaster. As a senior I have difficulty convincing myself and my peers that hard core survival skills will be possible or necessary. We can only prepare for those things we feel we have any chance to survive anyway.
To me, the best option is to store emergency food. How much? If you have none, store enough for a few days. If you have enough for a few days, get enough for a week. How much you store depends on what time frame you think you're at risk for having to be completely independent. The early settlers of the southwest liked to store enough food for a whole year and still do to this day!