Setup
Use https://edge-box.atlassian.net/wiki/spaces/SUP/pages/65543 to push content from a private staging instance to your production site.
Use https://edge-box.atlassian.net/wiki/spaces/SUP/pages/135135278 to automatically share content between any number of sites, in any direction.
Use https://edge-box.atlassian.net/wiki/spaces/SUP/pages/137232755 to push content from one site and allow editors to pull it manually into another site.
Content Sync is extremely flexible, so you can combine any of these use-cases with manual / automated push + manual / automated pull behavior, update behavior, different reference handling and a lot more. Check out the pages at the Flows documentation to understand all the options you have.