To turn on the New Meeting Experience for Microsoft Teams:

SWITCH TO LARGE GALLERY VIEW IN MICROSOFT TEAMS MEETINGS

https://drive.google.com/open?id=13DrxqsHh6JuBT_wSuoKmsSpWWwmXWb6-

https://www.marquette.edu/microsoft-teams/large-gallery-view.php 

https://www.marquette.edu/microsoft-teams/switch-on-new-meeting-experience.php 

Microsoft Teams 學習之路

https://sites.google.com/logosacademy.edu.hk/elearn/teacher/tools/microsoft-teams