Here are some helpful links:
The Early Intervention Program, A Parent’s Guide
https://www.health.ny.gov/publications/0532/index.htm
NYSDOH EIP
https://www.health.ny.gov/community/infants_children/early_intervention/
NY Connects: Early Intervention & Child Find
https://www.nyconnects.ny.gov/services/early-intervention-and-child-find-sofabroop12426