How do I go about receiving home care, and how much is it?

I was recently transferred from ssa disability to retirement age because I was over 65. I am now 67. I am also on Medicare and blue cross/ blue shield. I want to know the following: 1). How do I go about receiving home care. 2) is there a cost to me, and how much is it? 3) what if I cannot afford the cost? 4) can relatives or close friends provide the care? 5) can they live in the same house with me, and if not, why? 6) what are the qualifications to become a caregiver?