Here are the steps to crop a video in PowerPoint:

1. Open the PowerPoint presentation you want to edit and go to the slide containing the video.
2. Right-click on the video and go to ‘Edit Recording’. This opens the Video Tools Playback tab.
3. Select the ‘Crop’ option and enter a percentage in the ‘Crop From’ section.
4. The video will crop accordingly.
5. Click ‘Save’ to save the changes you made.