Can you help me for making a multi room?

Enter a description of your issue here, in full detail.
I want to make a kirby multi room but I can’t choose a preferred game. How can i add a preferred game??
In this massage, click on the plus icon in the game list but I can’t find any plus icon (I’m not good at english so my grammar will be bad sorry…)
System Information

  • Operating System: window 10
  • CPU:
  • GPU:
  • Citra Version (found in title bar): nightly
  • Game: kirby triple diluxe
  • Screenshot of Issue (include the full Citra window including titlebar):
    You must choose a Preferred Game to host a room. If you do not have any games in your game list yet, add a game folder by clicking on the plus icon in the game list

Diagnostic Log
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