How to Implement a Team Selection Screen in Godot 4.3?

Godot v4.3

Hi everyone,
I want to create a team selection screen in my game.
The idea is relatively simple:

  • The Team has 5 slots (you cannot start the game if the team is not full)
  • You (the player) chose the characters out of the ones you have unlocked
  • In the menu you can see the characters you have and the characters you chose
  • This team is the one you start the game with

How can I implement this in the best way possible?