Questions about Unitek Smart Charging Station

Yes exactly, it comes with an external power supply unit with a suitable power cable for a CH socket

They must be ordered separately.

approx. 2cm

The voltage specification for a USB charging station is not very meaningful. In principle, 5V is available at every USB connection, this is standard. https://de.wikipedia.org/wiki... There are fast charging technologies (e.g. QC / Quick Charge) where the device to be charged can request a higher voltage from the charger if the latter supports this. But QC also starts with 5V. https://de.wikipedia.org/wiki... With USB-C, there is USB Power Delivery (USB-PD) with which higher voltages are possible. Here, too, the output voltage is 5V. https://de.wikipedia.org/wiki... With fast charging technologies and USB-PD, the voltage is never specified, but the technology, e.g. QC 4 (Quick Charge 4).