Reference:
https://docs.microsoft.com/en-us/microsoftteams/teams-app-permission-policies

https://techcommunity.microsoft.com/t5/microsoft-teams/a-team-without-an-owner-notification/m-p
/1392209#M58518

See the solution in the explanation below:
Explanation:
To configure a virtual receptionist for your company's main office, you can use the Teams admin center to create and assign an auto attendant. An auto attendant is a voice menu system that allows callers to be transferred to an extension or a queue without speaking to an operator or receptionist. Here are the steps to create and assign an auto attendant that meets your requirements:
* Sign in to the Teams admin center with your Microsoft 365 username and password.
* In the left navigation, go to Voice > Auto attendants.
* Click Add (+) to create a new auto attendant.
* In the Basics tab, enter a name and an optional description for the auto attendant, such as "Main Office Receptionist".
* Under Phone number, select Assign and then choose a service number from the list or click Add new number to get a new one. A service number is a type of phone number that can handle hundreds of simultaneous calls and is used for services such as audio conferencing, auto attendants, and call queues.
* Click Apply and then Next.
* In the Greeting and menu tab, under Greeting, select Custom and then click Upload audio file to upload a recorded greeting message for the callers, such as "Welcome to Microsoft. Please listen carefully to the following options."
* Under Menu options, click Add (+) and then select Key press from the drop-down menu.
* In the Key press box, enter 1 and then select Dial by name from the Action drop-down menu. This will allow callers to press 1 for the company directory to lookup by name.
* Click Add (+) again and then select Key press from the drop-down menu.
* In the Key press box, enter 0 and then select Play audio file from the Action drop-down menu. This will allow callers to press 0 to hear the company address.
* Click Upload audio file and then upload a recorded message with the company address, such as "Our main office is located at 1 Microsoft Way, Redmond."
* Under Menu options, turn on the toggle for Repeat menu until caller hangs up or presses #. This will offer the same menu at all times.
* Click Next.
* In the Business hours tab, under Business hours, select 24/7 from the drop-down menu. This will make the auto attendant available at all times.
* Click Next.
* In the Review tab, review your settings and then click Save.
Now, you have configured a virtual receptionist for your company's main office that meets your requirements.