File Open

[thistlillo]

In the "File" menu, there are two items for the command "Open": see screenshot (I modified the shortcut for one of them to CMD+O).

The hotkeys pane of the preferences contains two items for the two menu items. There are no additional info here.

What's their difference?

[mikekazakov]

https://github.com/mikekazakov/nimble-commander/blob/main/Docs/Help.md#hotkeys
The first one enters the focused item, which has different meaning depending on the item type.
The second always open the item using default macOS associations.