With the cable direct method of connection and printing, since you won’t be able to access either the Polar Cloud user interface, or the Polar3D printer’s own onboard web user interface, you will need to run third-party printer control software on your device (typically your computer) that can control the printer. In particular, Repetier-Host is free software which can be downloaded and installed on your computer for this purpose.
You will also need an appropriate cable to connect your printer with your computer, such as a type-A-male-to-type-B-male USB cable to connect to your printer.
The proper type of USB cable looks like:
If you do not already have such a USB cable, you may purchase one from Amazon:
https://www.amazon.com/AmazonBasics-USB-2-0-Cable–Male/dp/B00NH11KIK