How do I find a player if I have his name with lowercase letters?

So I'm making a command bar, and for example, I have a kill command. The commands are seen from the textbutton.

My name is Player, and I have this text in the textbutton: kill player

What I want to do: -Check if there is a name "Player" in the game (with the text being 'player', not 'Player') -Kill the player if there is

What I've tried:

local textbox = script.Parent
local textbutton = script.Parent.ExecuteButton

local FindPlayer = function(plr)
    local newplrs = game:GetService('Players'):GetPlayers()
    for _,n in pairs(newplrs) do
        if (string.lower(plr) == string.lower(n)) then
            return true
        end
    end
end

Kill = function(text)
    if (string.sub(text,1,5) == 'kill ') then
        local trgPlayer = FindPlayer(string.sub(text,6))
        if trgPlayer and trgPlayer.Character then
            trgPlayer.Character:BreakJoints()
        end
    end
end

textbutton.MouseButton1Down:connect(function()
    Kill()
end)

Any help would be appreciated.