What is the difference between Selected Element and Other Element?

These are the advanced settings used when selecting a step while creating a Flow.

Selected Element: The UI element on which an action takes place. For example, the selected element could be a button or a menu that is clicked.

Other Element: The other element is any element present on the page on which the step is being created. It's used when the selected element does not have a unique identifier. So, the step can appear based on the presence of the other element.