Click on Text on the left side of an Edit Widgets panel for a widget you wish to update the text to.
Note: The Text menu is not available to every widget.
Widgets may display confirmation messages, error messages, or other messages when users interact with them. The Text menu lists each of the default messages used in the widget. To customize these messages and enter your own text, or to translate these messages into your users’ language, enter your own text into the fields in the Display this Instead column. When you're finished making your changes, click Save & Exit.