How to provide options with ugameplaystatics::openLevel?

Hi, I am building a dedicated server and I have a menu where people can host or join games. If someone click host, I want to open lobby level and want to pass the number of players he wants to have in the game so that I have logic in the lobby gamemode that will wait until those number of players are spawned in lobby and once the criteria is met, it will take to appropriate game map. However, I am not sure how exactly to pass the options and how to parse the options as well using ugameplaystatics::parse(). Any help on the syntax will be helpful. If this is not possible for my situation, then pls suggest an alternative as well. Thanks.

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