Welcome to BYC! It's great to have you. Giving a hen chicks can break her of broodiness, however in some cases she may reject and kill the chicks. It will depend on the hen. The chicks must be young (1-3 days) for introduction to be successful.
Some hens will go broody and some will not. While leaving the eggs in the nest may encourage a hen who is in the early stages of going broody; if a hen is not prone to going broody, no amount of eggs in the nest box is going to turn her.
If a hen is broody she will sit on whatever she can, including an empty nest, a rock, a fake egg; pretty much anything
Usually, with broodies, there is no doubt as to whether they are broody or not.
Some signs that a hen is broody are:
Sitting in the nest box for an extended period of time; only taking a break once or twice a day to have something to eat and drink and deposit a huge and rather smelly broody poop.
Fluffing up and/or screeching and pecking if you try to move her.
Stealing or gathering eggs from another nest box and sitting on them.
Choosing to sleep in the nest box rather than on the roost.
Constantly running back to the nest box no matter how many times you move her [not to be mistaken for actually wanting to lay an egg].
One way to test if a hen on the nest is broody is to place an egg in front of her; if she rolls it under and snuggles onto it, you likely have a broody.
I have some serious broodies
Planking because she can not actually get to the nest:
I think I have my 1st brooding hen! The nests are raised so do I need to put her on the floor in a somewhat protected area? I worry that she won't eat and drink. How many days will she set on her eggs? Any suggestions wound be great thank you!