Yes and No. A layout can and often is a layout but, sometimes you can still have all of your levels on a single layout. Aside from levels, a typical example of one my games project folder for layouts might look like and in this order run like the following:
Loading Layout ( My custom loading layout)
Start Layout ( The Splash Screen where a player has the option to Start Game or go to Instructions )
Instructions Layout ( Optional Choice this may also be a Story Board )
Level Layout ( Where the current achieved is displayed and selected )
Story Layout ( There may or may not be here and if so, it consist of 2 or more additional layouts )
Main Game Level(s) ( Where the main game play takes place. This could be 1 to 20 physical levels )
High Score Layout ( High Score / Leaderboard )
End Game Layout ( Where the user gets to Restart or Exit the game )
At least his is my approach. Pretty straight forward.