I am on phone(using browser) i will try my best to answer this.
Players.PlayerJoined:Connect(function(player)
    while true do
        while Players.Health == 0 then
              repeat wait(0.1) until Player.Health == Player.MaxHealth
              player.Position = Workspace["Checkpoint"..tosting (Leaderboard:GetPlayerColumnValue(player,"Level"))].Position
          end
     end
end)
Idk if this will work,
Here is what to do
Name your checkpoints depending on level
Like the level or obby is 10 then name part Checkpoint10
Hope this helps!