"I was 5 months pregnant when I met a man (obviously not the father), and started dating him. He wanted to marry me & raise the baby as it were his own. I married him right before the baby was born. The bio father wanted nothing to do with either of us and came to find out that he had another baby being raised by someone else as well. When baby was born, he signed the birth certificate. He ran off to NYC 2 months later and I haven't seen him since. The bio has passed away a few years ago. My husband of 10 years, and father to the same baby since 3 months old wants to 'adopt' him and have his name on the birth certificate. A) Where do I begin this process and B) Do I first have him removed and then take steps to adopt?

Contact the Family court in your area... they will tell you what you have to do and what you can't do. You won't do it without a lawyer or the court.

A) by hiring an attorney
B) Your husband will adopt, the legal father's removal will be all part of the adoption process. Your attorney will prepare all the paperwork

Of course the legal father is still considered the legal father and has all those rights until the court orders this changed,
In some places you can not even change it after periods.

So attempts to find the legal father ( one who signed birth certificate ) will have to be made. And if found and he signs away his rights it will be much easier.

And of course if you have been collecting child support, it would be easy to find him

Gather all the documentation you can for the bio father including the death certificate. Make sure it is a "certified" copy. Take it with you to a lawyer and present it to them. They can give you an idea of how to proceed. Is the child collecting social security from the deceased parent ?