Voicemails are recorded on your network as audio files and are downloaded to your phone. They are then played back in the usual way, just through the phone app rather than through the music app. Any voicemails you have are visible in the Voicemail app and should be able to be played back by pressing the play icon. This doesn’t always work, though. Here are some fixes you might try.
Important note: In some states, such as California, it’s illegal to record calls or conversations without permission from all parties involved. If that’s the case, ask your call participants if it’s OK if you record the conversation before you start recording. Then, ask again once you do start recording—so you have their permission on record. Alternatively, if you state “I’m recording this call for [whatever purpose]” and your contact stays on the line, that’s OK as well.

To search for the Phone app, when viewing the Home screen on your iPhone: – Swipe down on the centre of the screen > in the Search box at the top of the screen, type “phone” > the app icon will be shown (you can open it from there) along with any folder name, shown to the right hand side of the icon.
Here’s a simple clinician voicemail script if you want to keep your message to the point. Hello. You’ve reached Highland Family Counseling Services. We are currently unable to take your call, so please state your name, phone number, and a detailed message after the beep. We will return all calls within two business days.