Anyway fundamentals, along with cooking and swimming (even if you don't live near water) I would say knowing how to survive on a budget is a must. Knowing how to grow your own food and make ends meet when money is tight. We are all conditioned to expect food to be readily available for us in the supermarkets, every day of the year and we take it all for granted. Also knowing how to mend and fix things, instead of throwing them out and buying new stuff all of the time.
This is true, it’s something that most parents of my generation taught us as kids. We were all encouraged to cook and grow veg in the garden with pop and take care of the things we had. Great shout mate a manual for life in one paragraph.