That is why I encourage you to buy a few extra firearms in anticipation of this future need. I would suggest that a revolver is the simplest entry-level firearm to provide to a non-shooting neighbor. There are no magazines, safety catches or slides to learn to manipulate. You simply open the cylinder, insert the bullets, close the cylinder and the revolver is ready to go. A revolver has the shortest “learning curve” of any firearm. Anyone can learn basic gun safety and effective close-range self-defense with a revolver in one afternoon. In dire extremes you could hand a revolver to a non-shooter after a five-minute period of instruction and dry-firing. Revolvers are intuitive; you can even see if they are loaded or unloaded simply by looking at the cylinder.
Now that was written in 2019 when revolvers were cheap and plentiful, not in 2021 when you can barely obtain them. I wish I had gone to gun shows and flea markets back in 2019 and picked up 5-6 used revolvers but that is neither here nor there now. Simple is best. Revolvers, .22 rifles, pump shotguns. The SKS would be great if the price hadn't skyrocketed on them.
Like I said, Matt covered a lot of good points in a short time so jump over to American Partisan and read his post as well.