How to? Permanent character on server

Hello!
How can I do that multiplayer system:

  1. Server has list of players and on start loads it lets say from file, creates characters for all players
  2. User connects to session and posses to assigned character, then plays as usual
  3. Player can see/interact with all characters, including that offline
  4. Player for ex assign some todo list for character: mine diamonds, kill nearest enemy, cook bread… And than close session.
  5. Character on server side acts by list same as under user control, and is visible/accessible for another users in visibility range
  6. When characters list is done he stays at last point and awaits for his user session, maybe destroyed by timeout. But it still replicable for other players, lets say other player may hit him

So character is still “permanent” when server is working.