How to Start multiplayer game?

hey guys.
i am making a multiplayer game that has a countdown timer and time is important. so when session is created host player will go to the level and countdown starts, in this time player 2 joins the game with almost 6 seconds latency, and its behind from first player. so my question is what should i do to game that find out when to start?

i tried this but it didn’t work.

so what should i do? and where? (game instance or game state or game mode)
and i made loading screen but i cant connect it to both server and client. thanks for help

Use 2 trigger boxes, and make it so that when both players stand on each other trigger boxes, then start the count down

thanks, but i need something else because players wont stay in area (its vehicle) so i need something that knows the number of players in another copy of level (like lobby) and when its equal to max players (determined in menu) the game changes level to the map with countdown

Check in your game mode class, there is a PostLogin function, override it and keep a count of player when they join. Remember all the players joining your game will have PostLogin function called on game mode.

I hope that helps

yes thats helping. i am working on it from the last hour. what a lovely thing integer is : )))))))