Hover over the post and click Edit with Elementor.

If the image is in a separate Image widget:

1. Click the applicable image.

2. Click the dropdown arrow next to Caption, then click Custom Caption.
3. Add in some text. It will display beneath the image.
4. Click UPDATE (if this is a published post) or click the ^ up arrow next to PUBLISH and click Save Draft if this is a draft article.

If the image is part of a Text Editor widget:

1. Click in the widget to select it.
2. Scroll down to the image.
3. Click on the image to see the image menu then click the pencil icon to edit.

4. Add some text in the Comment Field.
5. Click Update.

6. Click UPDATE (if this is a published post) or click the ^ up arrow next to PUBLISH and click Save Draft if this is a draft article.