I have a 16 and a 17 year old.
I wash their clothes, when I wash mine, if they are in the washing basket. If not, it's up to them.
I iron school uniform, but anything else is up to them.
I return clean clothes in a pile for them to put away, which they do.
I cook them food if they are eating the same meals as us, which is mostly. If not, they cook and clear away their own. I'm still having to train them that if the dishwasher is full of clean stuff that they need to empty it, rather than just stacking their dirties on the side. They are a little resistant to this, but the message is slowly getting through!
I largely leave them to their own devices regarding their bedrooms, but I'll remind them if bedding hasn't been changed or hoovering hasn't happened for more than a couple of weeks, and they'll generally do it in the next day or two. They also need reminding to clean their bathroom, but will do a quick wipe over once reminded (not to my standards, but they're the ones using it).
On top of that they will offer to cook us food if they're cooking something, or pick stuff up from the shop if they're going there. They'll ask us if anything needs washing if they're (rarely) putting a load on.
They're definitely not fully functioning as adults, and they don't do stuff to the standards that I do, but they're gradually moving in the right direction. By 19 I hope they'll be pulling their weight fully!
(I'm using I as a shorthand for DH and I. He fully pulls his weight.)