Its ok, it takes time to figure things out. Modx has a lot of power, but also flexibility in how things are set up.
Ok so I wonder whether you are using google for ecommerce, its possible that everything is managed in google (I think).
Also, let’s talk about how your payments are processed, go ahead and click through like a customer would, to see the payment options. Another question is, does the site have a checkout cart for purchases? if so, you seem to be using a third party tool for that.
I think that the MIGX or the collections could have this data, again it might be called a counter, because its just a tiny tool that keeps adding numbers when its fired on the page. MIGX might be the most likely but i am really not too sure.
You might look into your list of tvs or snippets for information.
Please tell us more as you figure stuff out. Its a steep learning curve, to be honest, but its worth it because you can really control your site well with Modx.
We are here to help out, so no question is a bad one.