A Google business listing gets your business location and contact information registered with Google to improve search results ranking.
A common scam is via phone call with an offer to get your business registered with Google. They may pose as a Google employee and will charge you for the service, which they most likely won’t even do. Usually the phone # is faked too.
Google will never call you about your business listing. It is free to list your business and easy enough to do. If you get a phone call for Google business listing it’s best to just hang up.