I thought there used to be a sync option, but I'm not seeing what I thought it was.
When you create a new item, scroll all the way down and check the setting for "Square Online Settings" and make sure it's set to visible. You may see a blue box prompt to set up auto sync, or go to the online dashboard -> Items -> Item Sync and make sure the "Custom sync settings is turned on for "Automatically add new items to this site".
Also, make sure the default setting for "Item visibility settings" is set to Visible.
For Services, make sure the Bookable by Customers Online is toggled on when creating the service.
I typically just use checkout links and put the links on my main website. We sell photography and it's just easier that way for our packages. So I have it auto sync, but makes the items unavailable since a lot of our items are in-store only.
Let me know if this helps.
