Listen, we all have to learn, starting from the beginning---always collect eggs from Every nest Every Day---EVEN if a hen is on the nest----never pass/skip a nest-----then the First thing to do IF you want a Good hatch is to make sure the eggs----ALL the eggs under your broody are set at the same time----you collect the eggs and You put them all under her at one time---marking them clearly if she is going to be where other hens can get to her nest and they will probably lay other Eggs that YOU have to remove daily(they want be marked). Now doing this you have eliminated a Staggered hatch which is Not a good thing. When you get the eggs "set" under your hen mark your calendar or write the
hatch date over her nest----always start the next day as day 1 and count to day 21 for your hatch date---mark it then you want be wondering when that day is and you want be messing with the eggs during that time.
Hopefully they will be alright being you bothered them at this critical time?? As far as being ok with the rest of the flock---if you are going to allow them with the flock, you will just have to keep monitoring them to make sure they are not being pecked to death---Most regulars on here know How I feel about that----I never allow the young with the old.
When your eggs start hatching---she will probably leave the nest in a day or so with the hatched chicks---the "Good" unhatched eggs will die in the egg if YOU do not put them in a incubator to finish hatching or you can remove the chicks that hatch first to a properly heated brooder and keep removing them as they hatch and maybe she will stay on the nest and keep trying to hatch the others---which is Not a good Thing---that's why YOU should never Allow a Staggered hatch---its a Problem. Good Luck