To receive online orders into your Square For Restaurants POS, you must first enable the setting in the Square Dashboard on the website that will allow it to accept online orders.
Step 1) you will want to log into the web dashboard and located the section for Point of Sale from the categories on the top of the left-hand panel.
Step 2) On the Point of Sale panel, you will want to locate and select the POS terminal titled "Square Restaurant" followed by the location name and it will load the "Edit Device" settings panel.
Step 3) On the "Edit Device" panel, scroll to the very bottom to the setting "Manage Online Orders on Point of Sale", which you will want to enable. The button will slide to the right and change from grey to blue. Once this is enabled and you click "Save" in the top right, you will now be able to receive orders directly into your Square for Restaurants POS.