my hen just started sitting on 6 eggs last night but a day ago i put in 40 eggs in my bator by some miracle they all hatch can i put they out with her and her babyies should hatch about same time with in aday or two
Will broody hen adopt chicks
You can give her some of the chicks; a dozen or so. More than that she will not be able to keep them warm and safe.
You don't mention the size of your hen. I agree a dozen total for a standard breed, first time broody hen.
If it is a bantam, she may be maxed out at the 6, unless you are hatching batams, then you might give her 8.
I give first time mommies fewer, and definitely do not stagger the ages as it will confuse her and she may attack the additional chicks from the bator if she feels she needs to protect still unhatched chicks in the nest. Dud eggs can help keep the hen nesting as you add fosters, but if they are in the process of hatching, she may not like the interruption of additional chicks. It all depends on the hen.
Have a plan B if she doesn't accept them well.