How does one FIND an administrator t do something with?
Use the Citizen tab at the top menu bar. From there, there should be another menu bar up top that lets you go to the whole collection of citizens that you have. The symbols they use is a bit squirrely but tapping each citizen until you find an admin and click and promote using the button under their profile pic.
Alternatively, when you Train a Citizen you ReName each citizen with the Position they've been trained as: Administrator 1, Scientist 1 etc increasing the number as you create the next one in each category.
It's better than the alternative:
"Bob Roberts, report to my office!"
Bob Roberts: "Yeah, boss? How can I help?"
"No, not you, mate, you're a Scientist."
"Bob Roberts, has anyone seen him?"
Bob Roberts: "Hi, boss!"
"No, you're in Engineering. You're not what I need, dimwit!"
"Damnit, someone get me Bob Roberts, right now!" etc