Sign into Microsoft Teams with the account you wish to set up voicemail. This must be done if you are using a common area account that is not your own. If you are wanting to set this up under your own account, Microsoft Teams should already be signed in as you.
Voicemail Set Up
Select Settings from the menu (three dots) button
Select Calls, then scroll to the Manage voicemail section
Now, you have some choices:
You can record a voicemail greeting. This will trigger a call to your voicemail where you can record a message. Follow the prompts on your call to finish.
You can enter a text greeting. This text greeting will be read by the system for anyone who leaves you a message. This can be used in lieu of a recorded greeting.
You can change the language of your greeting. English (United States) is the default setting.
Also, since Teams is connected to your Outlook email account, you can have a separate text-to-speech message in place for when your status is set to Out of Office.
Managing Out-Of-Office Voicemail
Select Calls, then scroll to the Manage out-of-office voicemail section
You will likely need to change a couple of settings to ensure that your out-of-office voicemail is configured properly to sync between Teams and your Outlook calendar.
Uncheck the All the time checkbox.
By unchecking it, you can customize the other settings.
Check the When Outlook automatic replies are on checkbox.
This will sync your Outlook automatic replies with your Teams status and presence.
Check the When I have an out-of-office event on my calendar checkbox.
This will ensure that when an out-of-office event is on your calendar, that it will sync with your Teams status and presence.
For Mobile Application
Select Settings, then Calling
Scroll to the Voicemail section and select Change voicemail greeting to record a voicemail greeting. This will commence a phone call to record a greeting.
