Conditional Fields

Hi, I am very new to this and I am wondering how I go about making the following:

Select State (as a dropdown) then once they select a state it gives you the cities/shires in that state, then once city is selected it then gives you suburbs to select from.

I am trying to make an enquiry form for courier to show franchise areas available.
Once they select the area they want and have filled out their details they would submit form.

I am currently working with Contact Form 7 + Conditional Fields but I’m struggling. Thank you in advance for helping out a novice.