I found some videos for Microsoft Flow on youtube. All these videos are uploaded by Microsoft Team.
Microsoft Flow: Getting Started
https://www.youtube.com/watch?v=iMteXfAvDSE
Microsoft Flow Quick Look (0-1)
https://www.youtube.com/watch?v=2zN4hCVzXDU
Building Blocks of Microsoft Flow (0-2)
https://www.youtube.com/watch?v=KgINg0LiRf8
Microsoft Flow: Watch your flows in action
https://www.youtube.com/watch?v=3wPoUCGm7Yg
Microsoft Flow: Create a Flow from Scratch
https://www.youtube.com/watch?v=Gt3CMhLAQqE
Microsoft Flow: wait for Approval
https://www.youtube.com/watch?v=W6oxcYRtW-8
Introducing Microsoft Flow Webinar`
https://www.youtube.com/watch?v=EO-bGWIXjQY