If you don't need the full functionality of a mail server, or if you don't want to bother with the hassle (as running your own can be very time consuming depending on your mail load), services such as Mailgun and SendGrid exists to offload the burden by using an API.
Plugins for both exists for WordPress and work very well. When I was using WordPress, I used one or the other quite often.
You don't need a working knowledge of the API. The plugin will handle the API calls for you. All you'd need to do is install one of the plugins, sign up for one of the services, add an e-mail address for it to use and then enter the API details in to the plugin configuration.
This would be the best route to take unless you need a more detailed configuration or setup.
While the plugin won't handle it, it is possible to also work with Mailgun's API and send & receive e-mail. I've written test PHP scripts to connect, send, and receive using their API, so it is possible to use Mailgun to service pretty much all your needs as well.