Add a movie or clip in QuickTime Player on Mac
You can add whole movies or clips from other movies to your movie.
Add an entire movie
In the QuickTime Player app
on your Mac, open the movie you want to add to, then choose View > Show Clips.
Do one of the following:
Insert a movie at the end of the movie: Without selecting anything, choose Edit > Add Clip to End.
Insert a movie at the beginning of the movie: Without selecting anything, press Option, then choose Edit > Add Clip to Beginning.
Insert a movie elsewhere in the movie: Select a clip, then choose Edit > Insert Clip After Selection.
Find and select the movie you want to add to your movie, then click “Choose media.”
When you’re finished, click Done.
Add a new clip
In the QuickTime Player app
Choose View > Show Clips.
Select the clip, then choose Edit > Copy.
The selected clip is outlined in yellow.
Open the movie that you want to add the clip to, then choose View > Show Clips.
Choose Edit > Paste.
The clip appears at the beginning of the movie. Drag the clip to rearrange it.
When you’re finished, click Done.