Track purchases from customers/visitors

Guys, I have a problem understanding this.

I can award points, etc., via the dear good campaign.

But I could also be wrong, wasn’t it the case that you can also write data such as purchases, usage, etc. on the website via the Tag Manager in Mautic to the “visitor” like with the Matomo Tag Manager or Google Tag Manager?

So that I can also fill the customer with data that I can then evaluate later and then send the newsletter etc. even more specifically.

Where can I find that in the documentation or am I thinking wrong?

You can save ONE value in a Custom field. You can’s save multi dimensional sales data and make sense of it without a plugin (I don’t know about a plugin that does it.)
You can save: TOTAL SPEND: $200
You can’t save: 02.02.2020, $200 + 01.02.2020, $100 = $300