how to find the player who clicked a buttons' user id?

ok so title is confusing. How would I find the user id of a player that clicked a gui button?

function Click(player) 
	print("Terminal Works")
	if player.UserId == 293872889 then
	script.Parent.Parent.Parent.Access:Play()
	wait(1)
	script.Parent.Parent.Parent.Options.Visible = true
	script.Parent.Parent.Parent.LoginFrame.Visible = false
	else
		print("User failed to access a terminal.")
		script.Parent.Parent.Parent.Denied:Play()
		end
	end

script.Parent.MouseButton1Click:connect(Click)

If this is in a gui you should be using a LocalScript, so you can just do:

local player = game:GetService("Players").LocalPlayer

Also, MouseButton1Click returns the players mouse, not the player.

Hope this helps :)

local player = game:GetService("Players").LocalPlayer

function Click() 
    print("Terminal Works")
    if player.UserId == 293872889 then
    script.Parent.Parent.Parent.Access:Play()
    wait(1)
    script.Parent.Parent.Parent.Options.Visible = true
    script.Parent.Parent.Parent.LoginFrame.Visible = false
    else
        print("User failed to access a terminal.")
        script.Parent.Parent.Parent.Denied:Play()
        end
    end

script.Parent.MouseButton1Click:connect(Click)