If my husband relocates out of state for a job cani take my kids from a previous relationship?

You may be able to , but you wil have to apply to court to be able to do that.  You will have to provie that you can still keep up with visitation, and allow the children to see their father (if there is visitation now).  You also have to give proof about the job, that the move is better for your family, etc.  In other words, you have to prove that you are not just reloating to prevent visitation.