How Do I know If a Value(which comes from a textbox) is a string or not?

--I tried
local uis = game:GetService("UserInputService")
local byteFlag = 0
local xByte = 0
local yByte = 0
uis.InputBegan:Connect(function(key)
	if byteFlag == 1 then
		if  script.Parent.Text then
			xByte = script.Parent.Text
			byteFlag = 2
			print(xByte)
		end
	end
	
	if byteFlag == 2 then
		if key.KeyCode == Enum.KeyCode.Return then
			local yByte = script.Parent.Text
			byteFlag = 3
			print(yByte)
		end
	end
	
	if byteFlag == 3 then
		script.Parent.Parent.Position.X = script.Parent.Parent.Position.X + xByte
		script.Parent.Parent.Position.Y = script.Parent.Parent.Position.Y + yByte
		byteFlag = 0
	end
	
	if key.KeyCode == Enum.KeyCode.Return and byteFlag == 0 then
		--Blah blah blah code stuff
		if string.lower(script.Parent.Text) == "move" then
			byteFlag = 1
		end
		print("Yikesss")
	end

end)
--Im fairly new to this kinda coding Im tryna make a admin for the game, And I cant get pass this.
~~~~~~~~~~~~~~~~~****
I really need help I tried to search this on the internet but 0 results.

A textbox input will always be a string. You can check to see if the input can be formatted as a number with tonumber, like so

string1 = "56"
string2 = "hello"

print(tonumber(string1)) --Will return 56 formatted as a number
print(tonumber(string2)) --Will return nil as "hello" cannot be formatted as a number

same thing as that guy.

string = "pie"
if not tonumber(string) then

			print("no numbers!")
else
print("there is a number in there!")
		end

output: no numbers!

string = "64 carrots"
if not tonumber(string) then

			print("no numbers!")
else
print("there is a number in there!")
		end

output: "there is a number in there!"

The above methods are a way to figure things out but If I recall correctly, you can use TypeOf to find the type of value of something like so:

local string = "String"
local number = 1
local boolean = false

print(typeof(string))
print(typeof(number))
print(typeof(boolean))

1. string
2. number
3. boolean

Then you can do conditional statements to figure things out;

local Text = "Hello"

if typeof(Text) == "string" then
	print("It's a string")
end

Hope this helped!