Where do I put the script to assign one specific player to a team?

I am trying to create a game where there are two teams, a team of catchers and one team with just one specific player on it. I have the following script:

function onPlayerEntered(plr) if plr.UserId == "ReeowDiKitty" then
plr.TeamColor = BrickColor.new("New Yeller") plr:LoadCharacter() end end
game.Players.PlayerAdded:connect(onPlayerEntered)

But I have no idea where to put it and I have tried different places in Roblox studio and it has not worked. I am VERY new to this and I have not created a game on Roblox before and my Lua knowledge is next to nothing so please be aware that I have no idea of any technical terms. I have created my two teams and created the spawn locator blocks for each team and switched off the autoassign. Is there anything else I need to do?

Many thanks in advance, I'm tearing my hair out here!

According to my knowledge, you have a few mistakes. Edited version:

local Teams = game:GetService("Teams")
local YellowTeam = Instance.new("Team", Teams)
YellowTeam.TeamColor = BrickColor.new("New Yeller")
function onPlayerEntered(plr)
if plr.UserId == --------
then
plr.TeamColor = YellowTeam.TeamColor
plr:LoadCharacter()
end end
game.Players.PlayerAdded:Connect(onPlayerEntered)

1. You put a username instead of a UserId.
2. I think you cannot just assign their team color, I may be wrong, but the edited version should be correct.
3. You have to use :GetService() for Teams.