To add or replace the favicon of a WordPress site, follow these steps:
1. Prepare an image file for the favicon. The file should be in .ico format and ideally 512 × 512 pixels in size.
1. Log in to your WordPress site and go to Appearance > Customize.
1. In the left-hand menu, click on Site Identity.
1. Scroll down to the Site Icon section and click on Select Image.
1. Choose your favicon file from your computer’s files and click on Select.
1. Save your changes by clicking on Publish.
1. Go to your site and refresh the page to see the new favicon. It may take a few minutes for the change to take effect.
If you want to replace an existing favicon, simply upload the new favicon file to the same location and overwrite the old file. Refresh your site to see the new favicon in action.
