Most browsers use favicons to represent your website on tabs and bookmarks. Safari's bookmarks use touch icons or Webclips.
Your smartphone's home screen will also display them when your website link is saved.
Make a 32x32 pixel image for the favicon and a 192x192 pixel image for the Webclip or Touch icon when preparing your web icon image assets for upload.
Once you’re done preparing your image assets:
Open the Quick Menu
Search for General configuration → Website Logo & Favicon
Upload the images you prepared
Save for the changes to go live
Refresh your live site in your browser to see the updated favicon