Did you already check the "Radioddity extended manual for the Xiegu X6100"? I am not referring to the normal Xiegu manual, but to the 130 pages extended manual produced by Radioddity.
If you click on "GEN", you activate the softkeys that are related to the GENeral menu, such as "Radio Setting1", "Radio Setting2", "Display Setting", "System Setting" and "Memory Edit". You "navigate" by pressing one of those 5 softkeys.
If you click one of the other 5 function-keys "APP", "KEY", "MSG", DFN" or "DFL".you will be faced with different softkey definitions.