The most important thing in Odoo is to configure the product before you start selling. A product is used to define the stockable product, consumable product, or a service.
Other than the types of product there are many tricky configurations available on the product form that is required by the different applications, such as Income, Expense, and Tax configuration form Accounting application, routes and the barcode required by the Inventory application.
Note
The product configuration may change depending on the list of the application installed, on your instance. In my case, I have installed only Sales application.
Let's create a consumable and service type product to see how Odoo treats them and execute the business flow accordingly.
We assume that you are working on the duplicated instance, if not, create a duplicate instance and try to configure products on that.