Is the NCP docker image able to send email out of the box?

Is the NextcloudPi docker image able to send emailf from within Nextcloud?
When I go to settings->Basic settings -> Email server and use the sendmail option and try to send a test email it says Email sent, however there is no email received at the speciefied address of the nextcloud administrator.
Is this docker image able to send emails with sendmail out of the box?
Are there more configuration to be considered to get it work?

Sending mails directly is often blocked due to spam. So you probably have to send mails to a properly configured mailserver. Is there nothing in the documentation of NCP?

There is not much information about email in the ncp docs. For the php approach it says:

In Email server area of Additional settings select PHP as the Send mode and simply add the email of which you want to shown as the sender of the receiving emails.

For me it sounds as they configured the mail server. But maybe @nachoparker knows more about this topic.

@nachoparker can you provide more information on this topic?