There are no regulations that dictate the location of the affirmative action officer, nor their training requirements. But because the regulations are fairly complex, appropriate training will benefit your organization. The American Association for Access, Equity and Diversity (AAAED) has a good certificate program: https://www.aaaed.org/aaaed/Training.asp.
You can use this OFCCP audit checklist to ensure you're doing what is required to maintain OFCCP's regulations including VEVRAA, Section 503, and EO 11246. Or request a demo to streamline your compliance and recruiting efforts.