If the **** hits the fan, initially people will fight each other for what resources are left. But when it runs out we’d pretty soon we’d realise that we’d have to work collectively to survive, so that would mean growing food, collecting water, firewood, hunting animals, growing crops to feed pigs, sheep etc. For those who survived we’d probably end up going back to a lifestyle similar to our ancestors before the industrial revolution. That’s worst case scenario of course.
In the immediate aftermath of some catastrophic climate event. I’d forage for food on the beach, and eat mussels, limpets, crabs, seaweed, fish etc. I’d also forage for berries and nuts etc. I know where there are springs locally so I’d get fresh water. I’d also hunt rabbits and foxes etc.
Basic tenants of survival are food, shelter and warmth. I reckon I’d have those pretty well covered.