By default Ploi installs sendmail, but this is not configured.
You can however use sendmail, it is most likely that your e-mails will end up in the user's spam folder or even not get delivered at all. There are a lot of articles around to configure a mail server properly but it is a very intensive and long-time taking job to set this up. Besides that, it is hard to say if you will be able to build up a good reputation from the address you are sending from and get your own guarantee that e-mails will get delivered.
Therefore we have created this article to give you suggestions and help you out with e-mailing.
Recommended services to send e-mails
Postmark - https://postmarkapp.com/
Mailgun - https://www.mailgun.com
Sparkpost - https://www.sparkpost.com
Custom web hosting package with e-mailing (for example DirectAdmin has mailing built-in which you could use)
We can also recommend GSuite from Google, this is however a paid solution but you have quality software for e-mailing and high guarantee that your e-mails will get delivered properly. https://gsuite.google.com/
