Yup - you will not be running the CNC with your PC.
What they were referring to is DNC or "drip feeding"
This is a typical method of getting the program into the machine control that is too big to fit in the memory of the control.
The control (88HS) still runs the machine, it just simultaneously "pulls" the lines of code from the PC.
Like Scad is saying, with the 88HS (which is a good reliable control), you will very likely want or need CAM. You will also need DNC and a serial interface cable to go with the CAM. You may or may not need CAD.
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