How to connect ADB when device has no microUSB data port

I have an Android PC with root out-of-box connected to an external monitor (HDMI & USB).

While the device has a microUSB in, it's power only, no data - If I connect to the device's microUSB via a PC, ADB cannot see the device.

The device does have a Type-A USB port, but I am not sure how to get ADB to use it via the PC.

Yes, USB debugging IS ENABLED.