Keyboard shortcut

After creating a listed flashcard,how do I create a new rem in between other rem’s?

Hovering the mouse creates new rem when there is nothing downwards.
But is there any keyboard shortcut to do so?

Depending on what you want to accomplish: ctrl+alt+r on the newly created rem to disable them being part of the flashcard; enter or alt+enter, then shift+tab to create a new rem an move it an outliner level up.