@SteveCRF Thank you for reaching out to us, As I understand you are looking for a check box which says "User must change password a next login" when an admin resets the password from the Entra portal.
When an admin changes the password of the user, by default end user has to change the password, same is mentioned here on this screen
If you perform the same operation of resetting the password from Microsoft 365 Admin Center (https://admin.microsoft.com/) while resetting the password from here you will find these options
Hope this information help you, let me know if you have any further questions, feel free to post back.
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