Character Selection Screen

My simulation project requires a character selection screen for players and the automatic selection of a “ghost” flying character for the administrator. After the selection of the character (i need to load the character blueprint not only the mesh) the game must start with the selecter character.
I have created a selection screen but i am unable to make it properly work as it is always loaded the same character.
So two questions:

  1. How do i define the administrator’s character by default as a ghost (the character exists and the player - administrator discrimination exists using the switch has authority)?
  2. How do i select a different character (as a player) every time i log in to a game?

thnx in advance!