I've got a Hen and newly hatched chicks.. Now what?

[Bird Garden]

The Title says it all, I have 3 full grown hens, one of which is sitting atop fertilized eggs that I bought and two of the chicks hatched sometime today. I took my hen off to look at them and they both appear dry (and of course very small). How long should I allow my Hen to sit on top of newly hatched chicks? (She is sitting atop more eggs that are in the process of hatching as well)
I'm worried the chicks might not be able to breathe/ being smothered and also how they are getting nutrition. Should I move the hatchling's to an indoor incubator where they can get food and water now? Or is there a suggested time that they should just stay under the hen?
Also, I left their broken shells beneath my hen- my thoughts being that they may eat or need the afterbirth that is still inside the shells.

Please let me know your advice! I want all my chickies to be safe, happy, well-nourished, and thriving!!

 

[suzeqf]

Just let momma do her thing, This is what I do after everyone has hatched and nice and fluffy. I put mom and babies in a clean nest inside a large metal dog kennel that is covered with plastic hardware cloth so no one escapes and I put a feeder and waterer in the kennel I used a quail base so there is no chance of drowning. Usually after everyone is settled mom will get out of the nest and get a drink and something to eat and the little ones will watch her and do the same. They usually eat and drink about 24hrs after they hatch and if I haven't seen them drink I'll dip their beaks in the water just to make sure.