The text field will appear on the Stage and Timeline where you can start typing subtitles.
On the Timeline, a new Subtitle clip called 'Subtitles' will appear. This will be to indicate the subtitle track on the Timeline.
To add more subtitles move the red Playhead marker to a new spot in the Timeline to add new subtitles.
On the right-hand side of the Moovly Studio, you can change the properties of your subtitles. You can adjust the font, size, and (background) color and set a language for your subtitles.