How do I make it so when a match starts, the players will be taken from the lobby, to the map?

It depends on how you want to spawn the players really, but this might help you get a general idea.

function MovePlayers(...) -- function declaration
    local spawns = {...}
    for _, plr in pairs(Game:GetService("Players"):GetPlayers()) do -- iterate through table of players
        if plr.Character then -- if character exists, then
            plr.Character.Torso.CFrame = CFrame.new(spawns[math.random(#spawns)]) -- move their torso to a random spawn
        end
    end
end

-- usage
MovePlayers(Vector3.new(0, 0, 0), Vector3.new(100, 0, -100), Vector3.new(-400, 0, 50))
MovePlayers(Spawn.Position, Spawn2.Position, Spawn3.Position)

Make a teleportation script then set the coordinates of the 4 locations in the script, then set up the timer or random math function in the script. Hope this helped :3

plr = game.Players.LocalPlayer
char = plr.Character
brick = game.Workspace.Yourbrick -- change to your Brick
    char:MoveTo(brick.Position)

Here is an easy way