Editing the textbox.text help?

UIS.InputBegan:connect(function(input, proc)
    if input.KeyCode == Enum.KeyCode.Return and a == false then
        a = true
        local b = nil
        for i = 1,4 do
            wait(1)
            Item.Text = Item.Text..tostring(i)
        end
    end
end)

This is what it does... https://cdn.discordapp.com/attachments/476783279987490837/495667616116113408/unknown.png but... I want to do this... https://cdn.discordapp.com/attachments/476783279987490837/495667936170606623/unknown.png

if you know how to do that pls let me know :D

thx!