If Abobe would start implementing ready-to-use elements like these, letting them work for real, then very soon every one would start claiming tons of other widgets, gadgets, fidgets, whatever. That's not Adobe XD's goal. As a matter of fact, XD is more inclined to ley you to design it exactly the way you want it.
But relax, if that's too much of an effort, then there are also tons of templates and kits available, you can copy and paste from ! Just type in Google: adobe xd shopping cart templates and see them rolling onto your screen. Some examples:
https://www.xdguru.com/adobe-xd-ecommerce-templates/
https://www.behance.net/gallery/67085333/E-commerce-templatestore-themeshop-(FREE-Adobe-XD)
Keep in mind: you're designing the look, feel, and interaction – not building the complete thing. Any interactions like pressing a plus and seeing a number change, would require a few artboards to present these steps. So the artboard isn't technically the same thing as the final page or screen in the website or app. Artboards can represent separate interface stages as shown in one interaction.