I am not a prepper – https://en.wikipedia.org/wiki/Prepper although in the broadest sense of the term being prepared for a natural disaster I could be considered a prepper. I do live in an area that’s deep in Tornado Alley: https://en.wikipedia.org/wiki/Tornado_Alley, and having a tornado shelter, other than my creepy basement that’s full of brown recluse spiders and enough flying biting species of mosquitoes, gnats, etc. that makes it a place I don’t want to be if I need a safe place in the event of a tornado. I hope one day to buy a place and I would like to add something like Atlas Survival Shelters: https://www.youtube.com/channel/UCPf0hMaIoO2dyf3MDUTcCOg as a tornado shelter. Here’s their website: https://www.atlassurvivalshelters.com/.
They have some good tornado shelter options – https://www.atlassurvivalshelters.com/tornado-shelters/. They offer a variety of safe cellars including a wine cellar, fire shelters, bomb shelters, and tornado shelters.