I’d have thought most of the things you can do at home!
Pp is a great list. In terms of in the house I would start with them being able to care for themselves at home so:
Manage a budget for food shopping
Have some basic cooking skills which are also cost effective
Basic first aid for accidents when cooking or around the house
Washing, drying and caring for clothes including sewing on a button
Changing a bed, some basic cleaning tips.
What to do in various household emergencies such as to turn the stopcock off or go to the fusebox, what to do with a flaming pan or you smell gas etc.
I would then extend the financial element, so online banking, managing an entire budget, paying bills. Get them having a phone contract and shopping around for the best deal. Make sure they aren’t scared to phone customer services and query things or fill out forms, same with asking for help in a shop (have seen both be a problem for YAs).
Ensure they understand the services of a home so rates bills, home insurance, having a boiler serviced. All the boring stuff that they may have not seen happen because of their previous living situation.
Car maintenance, public transport and things like getting a passport probably depend on personal circumstances but all handy to know. Similarly some basic DIY like hanging a picture, put together some flat pack furniture, paint a wall and some woodwork, change a bulb and fuse.
If you have a pet, caring and being responsible for a pet is always a good life lesson.
How about making a list of all the unusual tasks you do over the next month and passing those on? Sounds like a lovely thing to do though!