I had college roommates who couldn't boil water. As a parent, I was not going to let my kids grow up without the skills they need. My kids started "helping" in the kitchen around age two. They had a tall step stool and they each got a "tasting plate" that we put a pinch of various ingredients on for them to get the idea of how flavors worked (only the safe ones to eat raw, obvi). They helped taste-test and name experimental jams.
Early things they could do included:
Pouring in things I'd measured
Mix by hand or turn on/off the mixer (under direct supervision)
"Decorate" their own personal pizzas
Fetch equipment and ingredients
Smash berries with a potato masher for jam
Choosing cookie cutters and cutting biscuits or cookies
This list quickly expanded to:
Scooping flour (with some help leveling the top)
Decorating cookies and cupcakes (frosting and sprinkles)
Cutting butter into dry ingredients with a pastry blender
Rolling out easy doughs like baking powder biscuits
Docking pizza crust with a fork
It's true that early on it was significantly more work to have them "helping" me, but that quickly changed. By age three it was the same amount of work or effort to have them helping as it was for me to make things myself. By four they were more help than work in the kitchen. By kindergarten both of them could read a basic recipe and could shape baguettes or make pizza from scratch with help on the oven.
We had rules for safety, I'm not an idiot.
If they couldn't see into a pot standing on the floor, they weren't allowed to cook at the stove. No falling into or onto hot surfaces!
Paring knives and peelers were used by only one child at a time to start and under close supervision.
At this point my kids are 20 and 17 and they each make dinner one night a week. They make everything from dumplings to quiche to curry to mac and cheese from scratch. On Sunday the oldest made dal by herself for the first time with only a little over-the-phone guidance while I was out of the house.
Kids love to learn. If they have the ability to listen and understand, they have the ability to learn how to make food. This requires patience and supervision early on, but results in teens and adults who are capable in the kitchen.