Go to Settings > Stores and select an individual store to update the following details displayed on your eCommerce site:
Store address
Store phone number and email
Store opening times
Go to Settings > My account to display your Company number and VAT registration number in the footer of your eCommerce site.
Update details
If you need to later update your details on this screen, you will need to go to Online Store > Online Setup and tap 
Publish setup info for this to update on the website.
