@talhaahmed-4938,
Can we simply create an user in office portal and assign her Microsoft business voice license for calling from app or web?
No, you cannot. When you try to assign only Microsoft 365 Business Voice license to users, it will show the following error message which tell us Microsoft Teams and Skype for Business Online licenses must be assigned.
we have a requirement where we only need a user to call using teams app on PSTN calling and we don't want to give them any access to email or SharePoint public sites in office 365 environment.
I also try to only assign Microsoft Teams, Skype for Business Online and Microsoft 365 Business Voice licenses to users, it shows the following error message.
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