One of the first things you might want to do when you set up a new Samsung Galaxy S10 is to record a voicemail greeting. Unfortunately, it's not obvious how to do that, so many people make do with the default greeting.
You can access listen to your voicemail messages from Microsoft Teams apps or phones, Skype for Business apps or phones, or Outlook apps.

After setting the number on your voicemail, you must also record a personal voicemail greeting. Follow the steps below. Start the Phone app. if you don’t see the numeric keypad, tap “Keypad” at the bottom of the screen. Tap and hold the “1” for about two seconds until the phone automatically calls voicemail. Immediately tap “3” to access voicemail settings. Listen to the options. On most voicemail systems, tap “2” to start the process to record a new greeting. The current personal greeting will play; then tap “2” again to record a new greeting. Say the greeting you want, and tap “#” when you’re done. To save the greeting, tap “1.” The personal voicemail greeting has been set. Hangup the phone. How to setup voicemail using a Visual Voicemail Applications
Access to voicemail can also be obtained through the iPhone’s dial pad by pressing and holding down the 1 key until your phone calls your 10-digit phone number, or by pressing the voicemail icon, which can be found in the bottom right corner of the dial pad screen, as shown in the image below.