Use response header property as a string

I am trying to use information returned in a header in a different method. Im using java and selenium, and i run a method that basically creates a game. This method sends a post request and it returns the following information.

Access-Control-Allow-Headers: Content-Type Access-Control-Allow-Origin: * Access-Control-Expose-Headers: GameId GameCode: fyguogzlui GameId: 5bf541ca33380b000f4b7a88

I want to then take the game id as a string and use it in a different method, i know i could change the public void method to a public string but i dont really want to do that, any siggestions