Nutrition for 8 week old kittens?

I have 3 foster kittens that I'm guessing are around 8 weeks old, at the most. I did not get them from a rescue. I rescued them from outside and am fostering them through a rescue. Anyway, I believe they were prematurely weened from their mother. They were being fed chicken wings by the owners.
I've had young kittens before, but they've always been weened from their mother and eating dry food by the time I adopted them. I also rescued a very young kitten, nearly newborn, and dropper fed him. Obviously, these kittens are a bit too old for that. Yet, I'm not so sure what to do for these guys. What sort of things should I be feeding them? They really need to get some nutrition I know they've been lacking for weeks now. What would you suggest?

moistened KITTEN dry with some wet /// if the vets says they are small for age add some formula ...

Take to a vet

I am well aware that they need to see a vet.
Since I'm fostering them through a rescue, I have to take them to a specific vet, meaning I have to wait until they can get me in. They aren't even open to make an appointment yet.

I'm using moistened kitten food right now. I think I will get them some kitten formula just for the extra nutrients. I was just wondering if anyone here has a similar experience and if something seemed to work well for them. It's obviously pretty common sense stuff. I just tend to be a little overprotective and worrisome about animals. I want to give them some kitten milk and such, but I wonder if they even need it since they seem to be doing pretty well with the dry food.

When I first got Mulder he was 7.5 weeks but very tiny. His mother rejected his litter at 3-4 weeks so he was weaned too early too. He ate dry food alright but since he was so young and small my vet had me soak his dry kitten food in KMR until soft and give him that 2x a day and then let him have dry kitten kibble to free feed the rest of the day.

I'd feed a high quality canned kitten food and some dry kitten food on the side.

Thanks to everyone for your suggestions!