To uninstall the app:

  1. Select Start, then select Settings → Apps → Apps & features.
  2. Select the app you want to remove (Fathom), and then select Uninstall.

https://i.imgur.com/kbsUieA.gif

To install the app:

You can download the Windows Desktop App by clicking: HERE!

See more information about uninstalling or removing apps and programs in Windows

here.