How to let video play manually in powerpoint?

I don’t know how to work with PowerPoint, this is my first time working with it. I have insert a video in the PowerPoint but when I preview the slide the video automatically plays, how do I not let it automatically play? I saw that some of my classmates did a PowerPoint with video but to start the video they clicked on it, that is what I want.

P.S The video is downloaded from YouTube, so that when I don’t have internet at my school I can still play the video in the PowerPoint.