Folder-structure view as seen on PC wanted in plexsrver

I‘m struggling to follow your description of icon.

Viewing a library by Folders

Plexamp

  1. Click the Library icon in the bottom bar
  2. Select Folders entry at the bottom of that page

Plex Web

  1. Select the music library
  2. Switch to the Library tab (if it’s not already selected)
  3. Set the library to display its content by Folders (instead of Artists, Albums or Tracks)


https://support.plex.tv/articles/200392126-using-the-library-view/

Play Queue

Plexamp

  1. Access the Now Playing pane.
  2. Scroll down to the Up Next section


You can interact with the play queue by long-pressing an item to access its context menu, or swiping the item to the left to remove it from the play queue.

Plex Web

https://support.plex.tv/articles/202188298-play-queues/