I’m more of the well-organised household type than Armageddon prepper, so I might not have the sort of advice you’re looking for.
I’m chronically disorganised (with possibly adhd) so it’s easier for me to organise family life in chunks - stocking up different categories at different times, than to remember on a weekly basis. Out of that base I can expand to manage looming crises (like covid) and contract to more manageable levels.
I only store what I can keep track of, and avoid wasting. But there can be lots of nooks and crannies in an average house - behind furniture, behind kick boards, tops of wardrobes, under floors, etc. You just need systems to keep track of what’s where (which isn’t my skill set). Some areas aren’t good for storage (attics fluctuate to extremes of heat, for instance).
I would absolutely love to build a bunker under our garden (and a network of secret tunnels) but dh is a bit more normal than me in that regard!
I think of prepping in terms of being flexible and adaptable. For me it’s not about creating a bunker and standing guard. I don’t and won’t keep weapons. Although I have trained in martial arts and encourage the dc to learn those skills. Knowing my limits is important.
I teach my dc basic skills, just in the course of everyday life, so that they could cope by themselves (even just to be able to cook and maintain hygiene if I was too ill to get out of bed) but without frightening them.
I build relationships and community- try and be a good neighbour, a good customer to suppliers (as close to the source of supply as I can), I watch out for vulnerable neighbours and family.
I have grab bags that have been used a couple of times for hospital trips. They’re not extensive but would help us cope for a couple of days. I keep my car in good shape, top up at half a tank, stay on top of maintenance. And we do have a rendezvous point for shtf situations.
I also think it’s very, very important to protect your mental health. It’s sensible to take precautions but after you do you should be able to relax and enjoy life. Stressing and obsessing about catastrophic scenarios isn’t healthy. The coronavirus crisis really brought home to me that a positive cheerful attitude is one of the most important assets when things go wrong. Be careful that you don’t get sucked into dark places when you’re learning about prepping.