How to apply for green card and health benefit for my father

You may not petition for a parent to receive an immigrant visa until you are a United States citizen. You must also be over the age of 21. You can find more information about petitioning for a family member at http://myattorneyusa.com/immigration-law-and-practice/immigration-to-the-usa/family-immigration. You should contact  agency that specializes in health benefits to see if your father qualifies.