You can send an email to the candidate by clicking the respective button at the top of the Candidate view, as shown below:
You need to fill the following information:
Subject: Select the country of the recipient's mobile number.
Template: Optionally select one of the templates you have previously created. The email body field will immediately be filled with the template's text.
Email body: Enter the body text of the email.
File: Optionally add a file to be send as an attachment.
Click on the Send button to send the message, which will immediately appear in the candidate's timeline.