Hi @Anonymous ,
There is no any function could check if all of a file has been viewed by a person in Microsoft flow currently,
If you would like this feature to be added in Microsoft Flow, please submit an idea to Flow Ideas Forum:
https://powerusers.microsoft.com/t5/Flow-Ideas/idb-p/FlowIdeas
I would suggest that you could let the teammate to manually create or update an item list a sharepoint list if he has viewed all of the video file. and you could create a flow to send an email when an item is created or modified in the sharepoint list.
Best regards,
Alice
Community Support Team _ Alice Zhang
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