how do you do...
 

the command /who <name> function in ui builder???

i would of thought it would be something like Onpress: who=parent.x.x.text (this is what i was trying, but im noob)

Try without the "=". ;)

Yep, try Onpress="who parent.x.x.text" since who is just a regular / command you activate it like any other (and give it the argument of the name).