After I have a signed POA for my fathers finances, what do I do?

Susan, we need more information. I see in your profile that your Dad lives in a nursing home. i assume since he is in a nursing home that he isn't writing checks to pay bills. Is your Dad paying for the nursing home from his own savings or is he on Medicaid?

Does he need help immediately or is this just part of his future planning? Is the POA the kind that takes effect immediately or do you need a medical declaration of incapacity before it comes into force?
What exactly is it that you want to do?