Looking to adopt

Im looking at adopting my family members child. My family member already has a few kids and just recently said they really dont want this child. They are a little hesitant on putting the baby up for adoption. I told them that I would adopt the baby if thats truly how they felt. I tried for years to have a child and its just not in the cards for me. If they do decide to let me adopt the baby where do I start on my end?