An insulin pump is usually covered by Medicaid if your doctor submits the forms that says you require an insulin pump.
My mom has to have an insulin pump and she has medicaid and her medicaid helped pay for the cost of the insulin pump so she didn't have to pay for the cost out of pocket.
However in certain states they have different policies so the insulin pump may or may not be covered with Medicaid and if not then you might look into other health insurance to pay for it.
Your private health insurance should also cover the cost of the insulin pump if you need it.
Your doctor should submit the forms and paperwork required for Medicaid or your health insurance to pay for the insulin pump so you shouldn't have to do much to get the health insurance or Medicaid to pay for the insulin pump.