DD1 (age 20) has pretty much moved out at this point. She sub-let in a flat close to her summer job last summer. I helped her move her things in from her university lodgings and asked her what she thought she'd be doing about food. Cue panic. We bought a small lodge pan and a baking pan, plus a sharp kitchen knife and a few pantry essentials. I sent her some recipes for simple meals and transforming of leftovers. She survived and no-one got hurt.
She had done a little cooking before she left home but knew nothing about the overall meal planning that is now second nature to me, what were basics for a variety of meals, what was a reasonable price for food items. You only get good at this kind of stuff by doing it. And really, I don't think it's all that complicated.
DS(17) always took more interest in the kitchen and cooks far more than DD1 ever did, but again he has never done the weekly shop or tried to stretch leftovers into another meal. When push comes to shove I'm confident that he will be well able to do it just as DD1 took to it. I chose not to push DD1 into kitchen duties when it really wasn't her thing because I was afraid of DS seeing his sister being taught this 'role' by me and shying off it himself. They all help quite a bit in the house according to what they're good at. DD1 would do the gutters with me while DS, who hates ladders, could get dinner together or do his laundry.
DS hates shopping though. I made him try on shorts and shirts the last time we went to get clothes for him, and intend to keep this up. I hope my efforts won't be sabotaged by some well-meaning GF or DP somewhere along the line.
I rarely bought clothes for exH because exMIL took care of this for almost 20 years of marriage and still does now that we're divorced
. He occasionally bought clothes for himself; disastrous results (his taste is old mannish or pimp with nothing in between). When he did the laundry I could count on things being ruined, and when he cooked everything was raw in the middle (no patience) -- he felt very competent and gung ho about it however, and resented it when everyone took their dinner to the microwave.