Yes that makes sense, simply copying and pasting code from the plugin into your page will not work.
You will only see exchange rates when they are loaded. This is why the debug windows are provided. So you know if the exchange rate was loaded or not. The exchange rates might not be loaded immediately after selecting rates providers. They will be loaded on the next run as determined by the time interval you have set.
You must also make sure that you have selected a currency to display. See the documentation under “Exchange Rates” for more.
kind regards