Creating Scoreboards

Here we have an example that will give all players a scoreboard and update it with a player counter Note Java and bedrock sorts scoreboard lines differently

function PlayerJoinEvent(event){
    var player = event.getPlayer();
    player.sendMessage("Welcome to the Server!");

    //Here we set a simple variable to be the amount of players online.
    var online = server.getOnlinePlayers().size();
    //Here we set another simple variable to be our max players amount
    var maxPlayers = server.getMaxPlayers();

    //here we create our scoreboard
    var sc = scoreboard.create();
    //here we create an display / objective
    var dp = scoreboard.newDisplay(sc, "Test Scoreboard");
    //here we add some lines to our display / objective
    scoreboard.setLine(dp, "Hello "+player.getName(), 2);
    scoreboard.setLine(dp, "There is currently", 1);
    scoreboard.setLine(dp, online + " out of " + maxPlayers, 0);
    //here we set our player's scoreboard to our new one
    scoreboard.set(player, sc);
}

manager.createLoopTask("scoreboardUpdate", 5*20);

function scoreboardUpdate(){    
    //Loading all online players into a array that we later can loop
    var players = server.getOnlinePlayers();
    //Here we loop our players array where the player variable will be players[i]
    for(var i in players){
        //Here we make it simpler to understand with making a variable to be players[i]
        var player = players[i];
        
        //Here we set a simple variable to be the amount of players online.
        var online = server.getOnlinePlayers().size();
        //Here we set another simple variable to be our max players amount
        var maxPlayers = server.getMaxPlayers();

        //here we create our scoreboard
        var sc = scoreboard.create();
        //here we create an display / objective
        var dp = scoreboard.newDisplay(sc, "Test Scoreboard");
        //here we add some lines to our display / objective
        scoreboard.setLine(dp, "Hello "+player.getName(), 2);
        scoreboard.setLine(dp, "There is currently", 1);
        scoreboard.setLine(dp, online + " out of " + maxPlayers, 0);
        //here we set our player's scoreboard to our new one
        scoreboard.set(player, sc);
    }
}