Kill command

for i,v in pairs(game.Players:GetChildren()) do
  if v.Name == "bobopopcornboy” then
    Plr = v
  end
end

Plr.Chatted:Connect(function(msg)
        local FirstWord = string.sub(msg, 1,5)

        if FirstWord == ":Kill" then
            local User = string.sub(msg, 7)

            for i,v in pairs(game.Workspace:GetChildren()) do
                if v.Name == User then
                    v.Humanoid.Health = 0
                end
            end
        end
    end)