"Cores" = the term used for the computer brain that does the actual work. The i5 (and some i7) Intel chips have 4 cores on them. Most i7 have 6 cores. You don't want a dual core; that is old technology. Think of Cores as "how many sprinklers are running at the same time?"
GigaHertz = Speed. Think of "how fast is the water coming out or those sprinklers?" High pressure or low = speed.
Memory and Disk and graphics card memory = Space = how much Room is there to store and process how much data? Graphics cards also have a speed consideration = how fast does the screen handle image refreshes, moving the mouse, opening a new window, etc.
I see this System Requirements page has Minimum and Recommended:
https://accountants-community.intuit.com/articles/1859689-system-requirements-for-2019-proseries-and...
You want to shop for i5 or i7; I am currently sitting at a laptop with i7 rated as 2.20GHz speed, for instance. Look for 8th or 9th generation; it's part of the Coding, as in "Intel® Core™ i7-9750H 6-Core Processor 2.6GHz" shows this is 9th and 2.6GHz. But, not this: "10th Gen Intel® Core™ i7-1065G7 Processor 1.3GHz" because that isn't up to the minimum speed of 2.20 GHz. If you want to try 1.8GHz, you might not notice any issues; I would never go as low as 1.3GHz, when Intuit recommends at least 2.20GHz.
Hope that helps.
