If you only have one brand in Centra, choose it here and all new products will use it.
Choose from the list – it shows the brands in your Centra.
Good to know
If the list is empty, check that Centra is connected. An empty list almost always means the connection, not the setting.
If a brand is missing, create it in Centra first, then click Clear Cache on the settings page so the list is refreshed.