Hi there,
first off, Favicons are heavily cached by browsers so the following may not work immediately.
You would need to:
1. Remove the Favicon from the Customizer > Site Identity
2. Create a Hook Element:
https://docs.generatepress.com/article/hooks-element-overview/
Add the following code to the hook text area. And add your FULL URL to your current favicon image.
<link rel="icon" href="https://domainname.com/uploads/2020/10/10/favicon-32x32.png" />
Set the Hook to wp_head
Set the Display Rule > Location to Entire Site
Set the Display Rule > Exclusion to the page you want a different icon for.
3. Repeat step 2 but this time add the page specific icon you want, and set just its display rules to the page you want.