How do we teleport a group of players in a SAME server in a place?

Make sure the PLACE you are going to teleport into is in the same GAME

If you don't know what that mean A GAME can have multiple PLACES, a starter place where the players spawn and branch places where they can teleport to

if you want to teleport from a GAME to a different GAME, then you need to put id of the STARTER PLACE from the GAME you wan't to teleport to

In order to let a group of players to go to the same place, get the children of Players - GetChildren() or you could make a table with their User ID's , then you can simultaneously teleport them all to the same place in the same game.

function teleport()
 -- teleport players
end

local players = {} -- have their ID's

for i, v in pairs[players] do
       teleport()
wait(1) -- teleport them with 1 second intervals
end

Hope it helps!

AltNature [Lua / Blenderer]#2828

OR this might work too!

You can use RemoteEvents to have the client tell the server teleport all the players.

Server

local placeId = 123
local leaderUserId = 1

local partyPlayersList = {
   game:GetService('Players').Player1,
   game:GetService('Players').Player2
}


game:GetService('ReplicatedStorage').TeleportSquad.OnServerEvent:Connect(function(player) -- Connects a function to execute when the "TeleportSquad" event is fired

   if player.UserId == leaderUserId then -- Checks if the player who clicked the start button is equal to the party leader
      game:GetService('TeleportService'):TeleportPartyAsync(placeId, partyPlayersList) -- Teleports all players in "partyPlayersList"
   end

end)

Client

StartButton.MouseButton1Click:Connect(function() -- Connects a function to execute when the client clicks the button
   game:GetService('ReplicatedStorage').TeleportSquad:FireServer() -- Fires the remote event
end)

    for i,v in pairs(game.Players:GetPlayers()) do -- gets every player in the server
    game:GetService("TeleportService"):Teleport(game.PlaceId, player) -- teleports them to the same game
    if player.Character ~= nil then
        player.Character:remove()
    end
end