Water is no problem here....very first issue I tackled 30 years ago. Two 1500gal tanks constantly refilled by gravity feed from our spring, which then gravity feeds the house. Pressure isn't the best (about 25psi), but we lived with it for decades before I finally put in a nice booster pump. I did not put that on the backup power panel, but would just flip a couple bypass valves and go back to lower pressure if depending on backup power.
Food is no problem. We have 6 smaller freezers, because as we empty them down, we shut one off. I do this because the chance of a failure would not take out a huge portion of our frozen food.....and as I pointed out to someone that once gaped in amazement: "We ALL have the same amount of freezer space....in my case, it's right here under my control....in your case, it's at the supermarket, warehouse or manufacturer's place...and it takes you multiple trips to the store to access it"
We also can and root cellar quite a bit, and could can a lot of the meat out of the freezers if need be, getting down quickly to one-two. And keep many cases/buckets of long term dehydrated foods, and dried whole grains.
One of several dry storage areas:
Root cellar....late summer, not to stocked yet.
Also raise our own beef, pork, chicken (meat + eggs), catfish. (Got steer in quarters in the walk-in cooler right now, to be cut up in another week or so)
Have two greenhouses we can grow 3+ season in.
Heat/etc: We now heat with wood 99%....use couple of super energy efficient mini-splits early fall/late spring when don't want the full heat of a fire. They are there mainly for some AC the few weeks of summer it's needed. I keep 12-15 cords of hardwood cut ahead....yesterday I was cutting wood for the winter of '19-20. Have a propane space heater that will keep the house well above freezing if needed, and 3-500 gallon tanks of propane (typical use for all propane is about 300 gal/yr). Range top is propane, water heating is propane (switched from electric after a 2 week power outage in a 90's snow).
Power: 11kw solar with battery backup, plus an 8 kw diesel generator with 1,000gal fuel storage. Another 8kw gasoline welder generator (Miller Bobcat). Plenty of stored gasoline preserved with PRI, and rotated/refilled regular into 300gal gravity feed tank for use around the place/vehicles.
Toilet paper ? Yeah.....big fan of it.

Got on a kick about it some years back, and put a dozen plywood boxes like this (144 rolls per box) well sealed and stuck in around in various sheds/barns).
Lots more, deep and wide..and plenty of defensive measures to hold on to it.......this is but a sample.