How to autopopulate text field & price field based on previous field entry

I would like to have users either select or autopopulate an answer from a predefined list of nearly 300 Counties. Based on their selection, I would like to have two fields updated. A text field and a price field.

It seems that this was done here: https://www.jotform.com/answers/308315-How-to-auto-populate-while-typing/?entrymessage=10732640770

But, the final answer is not shown. Can you help?

Thank you!!

My colleague has already provided an answer for you here:

https://www.jotform.com/answers/901150

Please avoid creating multiple threads with the same question.

Thank you