Then Search for User> Click on New Guest User
|New Guest User|
Enter the email ID and comments and then click on Invite.
Check for the user:
Now go to your D365 FO URL like below:
Now go to System Administration >User> Click on Import user
Now assign the desired role.
So it’s Done!
License: This will depend on what License for Microsoft Dynamics 365 Finance and Operations you have taken, always concurrent users should not be greater than the License procured by you!
Azure Guest User Limit: The limits of users to be added to AAD
A maximum of 50,000 objects can be created in a single directory by users of the Free edition of Azure Active Directory by default. If you have at least one verified domain, the default directory service quota in Azure AD is extended to 300,000 objects. See Azure subscription and service limits, quotas, and constraints.