To paraphrase The Clash, “Should I Stay or Should I Go Now?”
Prepping includes being prepared for all reasonable situations. The most likely situation is you are away from your home/supplies because you’re working or shopping. The difference is “are you at work and need to get home to your supplies,” or “I need to get from my home to my supplies cache (cash-ay).”
EDC Bag
Your Every Day Carry gear is either kept on your person or goes in and stays in your car. If you’re at work (or anywhere away from your home) and there’s an EMP/nuclear attack/sunspot and your car is disabled, you’ll have to “hoof it” (walk) home. Design this kit to do that job to keep you going for the 1-2 days it will take to get home. I have an article My EDC to get home [], which has my supplies that I would use to walk home, be it 5 miles or 500 miles. Don’t copy my EDC kit. My skills, capabilities and requirements are different from yours. Rather you should use mine to inspire what YOU need.
A search engine search for “EDC kit” or “EDC bag” will find you plenty of lists. You want your kit to balance lightness, yet be as comprehensive as possible. Most importantly is your kit needs to be inconspicuous. You will be walking 5-500 miles to get home and a lot of people will be sharing this experience with you. If you have a military-grade Army digital camo pattern backpack with MOLLE all over it and you have a dozen items swinging off it, you might as well paint a target on your back. You are openly displaying that you (supposedly) know what you’re doing and you have the supplies that everyone else probably doesn’t have. This means everyone you will encounter will “want to be your friend” so you share with them, or kill you for your supplies. It’s better to go low-key and blend in with something like a laptop-backpack like what everyone else has.
BUG-OUT BAG
This bag is meant for “getting out of town” at a moment’s notice in a Localized/Regional situation where you can be expected to return home fairly quickly, 3-5 days. The original intent by those who pioneered the concept was to permanently “bug out” in a grid-down situation. After a lot of people started thinking about this, they realized that by “bugging out” they actually abandoned 90% of their supplies (and 90% of their chance to survive). And even if they had a trailer to carry everything to a fallback position (property/friends away from cites, etc.), a couple of flat tires left you with no way to carry all of it again. Or having to sleep in the vehicle would make you vulnerable to raiders.
My point is, you do need a bag (for each family member) that has everything they need for up to a week. If a hurricane, wildfire, or other localized calamity causes a mandatory evacuation order to be issued for your community, grab the bag(s) and head to a designated friends’ house, or hotel that you can make reservations at. Just don’t think or plan for that bag to keep you running in the wilderness indefinitely.
DON’T FORGET TIP: If your vehicle runs on Regular gasoline, and you need to top off your tank before you head out (NEVER let your fuel level ever get below a half-tank), fill it with the highest grade the station has. It will likely be the only grade left if you’re running behind in filling your tank anyway. One or two tanks will not hurt your car, in fact it will help clean unwanted deposits out of the engine. Just don’t make it a steady diet if the car doesn’t need it.
If you have an old non-electronic vehicle with a carburetor, the good news is 1) it will keep running after an EMP, and 2) you’ll get more miles from that tank. If you normally get 300 miles to a tank (cars are designed to have a 250-350 mile range on a tank, no matter the MPG of the vehicle), filling it with Super (from empty) will get you an extra 50-75 miles to that tank. The cents per mile stays the same, but more miles. This extra distance could be what you need to get out of the disaster zone to your destination or find more fuel to keep going. This does not work with the computer-controlled fuel-injected cars and trucks of today.
The best thing I can say is you need to figure out when to bug out and when to bug in.