Adds a new list or site column using the CAML field definition

• command: spo field add -u|--webUrl <webUrl> -l|--listTitle [listTitle] -x|--xml <xml>
• webUrl: Absolute URL of the site where the field should be created
• listTitle: Title of the list where the field should be created (if it should be created as a list column)
• xml: field XML

For more information see the Add-PnPFieldFromXml cmdlet