Run, don't walk, to an attorney who specializes in international adoptions.
If you can find one who has done adoptions from Africa that is better, and from the same country would be ideal.
It is impressive you have gotten this far without an attorney. But you need one now. Use the search function on this site to look for lawyers who handle international adoption.
This answer DOES NOT establish an attorney-client relationship. This answer is based on the limited information provided and is not intended to be conclusive advice. There are likely other factors that might influence or change the advice after a more lengthy consultation.
I added an International Adoption link to your question. I guess you could start by looking at State Department or other websites that talk about the standard of living, and average earnings of people of that nation for some background. If you went through an adoption agency, I would think that they would be your best resource.
This does not establish an attorney/client relationship
You need to talk to the adoption agency legal department. If they cannot help, then find an attorney in your area who has experience in international adoptions. You could also contact immigration and ask what sort of documentation they require.
I recommend that you talk to an attorney in your area.
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