To edit email body you can use RTE / Text area control. For diff. types of RTE configurations please check the UI gallery(Pega 7). To send the correspondence you can use SendEmailNotification activity which is capable of sending emails to multiple mails ids.
Hi thanks for the suggestions, I need to show the correspondence in edit mode itself, as I would need to add WO link as well. so User can see the link and correspondence before sending and can edit if needed?