TextBox.Text is always empty?

Hmm.. where is this script located, if it's in a button im assuming u want it to print the text value? Also make sure it's a local script.

script.Parent.MouseButton1Click:connect(function()
	print(script.Parent.Parent.Coins.Text) -- points to a textlabel to grab the text data from and print it when u click
end)

This is what I usually do, and your script may work, it's just not a local script, I cant help your current script because i'm confused what the variables are and what they are pointing to.

Hm.. Try This: I'm assuming u want it to change the text to the coin change when clicked?

local player = game.Players.LocalPlayer -- this line was changed. Now connects to player
local coins = script.Parent.Parent.CoinsAmount -- connects to the text
local CoinChange = game.ReplicatedStorage.CoinChange -- remote event


script.Parent.MouseButton1Click:Connect(function()
    coins.Text = player.leaderstats.Coins.Value
    CoinChange:FireServer()
end)

Please read below for the errors i found:

Your error is very simple to point out, 'CoinChange' is not a part of workspace, it's in replicated storage, but u put workspace.CoinChange, which may result in a not written error. also, how can text be a part of a remote event? Also, a value cant be part of a remote event or text value at the same time! Also, player cannot connect like that.