Vee Ridgley
That's a WP function, go to Appearance > Customize > Site Identity > Site Icon.
I prefer to have the site favicon on the frontend but leave the backend with the default WP one. So I can easily differentiate between tabs when working on a site.
To achieve this go to BD Settings > Custom Code > Header Code > and add the following:
<link rel="icon" href="https://your.domain.co.uk/wp-content/uploads/2023/04/your-favicon.png" sizes="32x32">
Having created your own favicon and uploaded it the media library of course :-)
robotdance
If you setup BD to use Themes and use the Blank Theme from BD (on git) you could add a Favicon in the Customizer (this is WordPress default behaviour).