I was really worried about this too. I got my baby silkies today and I’ve been following this thread. I was able to get most of my guys drinking by pecking my finger in the water. Two of them arrived a little listless, so I gave them electrolyte laced water drop by drop with a disposable pipette. They really perked up after that and when I set them back in the brooder they went to the waterer and drank more without me needing to show them where it was. Sorry to answer with just an anecdote, but I don’t have much experience to draw from. Hopefully your guys are doing well.
If you have a gravity feeder, try tapping the container until they explore the source of the noise. Once they see the food, instinct kicks in. If any need extra help, dip their beaks in the water and food.
So mine have a brooder plate, gravity drinker and food trough.
They seem to only come out from under the brooder if I entice them to so only time I'm seeing them drink or eat is if my hand is in there guiding them.
They are plenty warm so not a heating issue.
Hoping they will learn to venture out solo soon.