The person named in the will would have first priority.
If no will exists-a personal representative may be appointed with consent of the beneficiaries
if quaified by NY law.
The answer given does not imply that an attorney-client relationship has been established and your best course of action is to have legal representation in this matter.
Assuming your father is a US citizen, he can petition for letters in the county where his brother resided. He does not have to appear in court personally. You can certainly help him, but you can't represent him unless you are a lawyer. What exactly needs to be done depends on whether there was a Will and the nature of the assets. How easy or difficult it may be depends largely upon the Surrogate's Court where the application must be made. Some courts are helpful, some not so much.
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