Announcement Bar
An announcement bar is a short snippet where you can showcase a message to your site. Using an announcement bar on your website is one of the easiest ways to draw visitors' attention.
Steps
In the theme editor (Customize), click Announcement Bar
Locate Announcement Bar
Make necessary changes
Save
You can control how the bar displays by ticking/unticking the checkboxes.
You can change the text and background color of the notification bar.