Emails are sent by default from a noreply@pendula.net address, and the sender name as your business. The sender name and reply to address of an email can be customised at any time under the Custom sender settings of an outbound email node. See Configuring conversation nodes for more information.
Additionally, the Pendula platform can mask emails from an internal business address or domain once this has been authorised by you. Please raise a support ticket if you are seeking more information on domain masking.