Let me share some insights on the difference between category details and item details.
Category details refer to the accounts listed in your chart of accounts based on the chart of accounts. An example of this is recording bills such as electricity and water bills.
On the other hand, item details are the products and services that you purchased from a vendor or sell to your customers. This also refers to adding an items by quantity and unit price. It may also help to use for some job costing purposes.
I've got this article that may help you in creating transactions in QuickBooks: What is the difference between bills, checks, and expenses?
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