There is
User Manual in
Details page of the web site. Details page also lists the package contents which is just the device unit. Many users use own cables, therefore instead of bundling some basic cable which would create additional trash in the World there are more
advanced USB cables offered at additional cost.
The side wit 2 ports is the one to which you connect your USB device (USB DAC, ...), and the side with one port is connected to USB host (PC, TV, Streamer, ...). 2-nd Micro-B port is only for additional isolated power delivery, in case USB DAC requires >400 mA. It is explained in User Manual.