TextButton makes Part appear

Help and Feedback Scripting Support
2

That should be a very simple script.

local TextButton = -- your text button

TextButton.MouseButton1Click:Connect(function()
    local Block = Instance.new("Part")
    Block.Anchored = true
    Block.Parent = workspace
end)

This should be a LocalScript.

If you’re looking to show the block to the whole server, then you’d have to use a RemoteEvent.