To get the caption track, use view show caption track, and to see the caption. While playing the video, go to View show captions. Now you can highlight a section on the caption track and enter the caption text that will be displayed during the portion of the video. some tricks here, one you can use dictation to enter the text quickly. You can even put dictation to listen to your text and automatically add the text there, too. You should synchronize the captions with the gaps in your audio recording so the text stops when you stop speaking.

And the last week, when you click on the caption added to the caption track, you can use Command and up or command and down to increase or decrease the caption length. Now let's play the video. And here are the captions. You can also right click on the caption track and select extract port to SRT The file will contain the subtitles for the video.