Ensure the e-mails are sent, what do I need to set?

Emails are sent e.g. at password reset, notifications and appointment invitations.

The email configuration can be found in the settings, you must be logged in as admin. In your cloud, click on your avatar on the far right, then Settings and there Basic Settings.

The default setting looks like in the screenshot. With this setting you should be able to send e-mails. You can test it with the button "Send e-mail".

Better than the default setting is to use your own mail server. This way you will get feedback when emails cannot be delivered.