The telephone systems have the feature named as Voicemail. VoIP is the best example of it. When a receiver is unable to pick up the phone, then the caller can leave the voice message on the receiver’s phone. In older telephonic machines, such messages were stored as a voice message directly, and the receiver can hear them later. In modern telephone systems, such info is being stored on the server of the service provider in the user’s mailbox. It is similar to email in which the messages are saved in the form of audio instead of text.
With visual voicemail you may not remember how to call voicemail to set it up. We’ll show you how to record a new iPhone voicemail message and listen to your current one.

Step 4. Begin recording your custom voicemail message by tapping “Record.” You can also listen to your recording by tapping “stop” and “play” before proceeding to the next step.
Assuming you only care to hear from a handful of people, open your phone’s Settings, and tap on Notifications. From here, tap on Do Not Disturb and toggle it on. Now, you can tap Allow Exceptions and add the contacts you’d like to get calls from.