To add transitions between segments of your clip:
Open your clip in the editor by clicking the edit button.
On the timeline, click on any segment you want to add a transition to.
When you select a segment, a video panel will open on the right side of the editor.
In this panel, you can add an enter animation (for when the segment starts) and an exit animation (for when the segment ends). These animations act as transitions between segments.
Repeat the process for each segment you want to animate—click each segment on the timeline and add the desired enter and exit animations.
Preview your clip to see how the transitions appear between segments.
When satisfied, click export.
For a step-by-step visual guide, see the attached video.