Add "region" field to request template

Add "region" field to request template

Hi,
 
We are currently reviewing our current setup of ServiceDesk Plus to better suit our needs in our organization. Our organization is active in 18 countries around the world, and each country have a number of clinics. In total we have more than 285 clinics.
 
We use ServiceDesk Plus as our main IT Incident reporting tool for end users where the tickets are then dispatched to the Local IT personnel in the various countries for them to action. In most countries there is only one team of Local personnel but in larger countries there is for instance one team in the southern part of the country and one team in the northern part. To facilitate our current setup today we have setup the different countries as "Sites" in ServiceDesk Plus. This however makes all the 285+ clinics appear in the list of "Sites" when a user is creating a new ticket
 
We now want to change this setup to include 'Regions' instead, which is already pre-defined in the setup of ServiceDesk Plus.
 
Example:
Region France
  - Clinic Lyon
  - Clinic Paris
Region Sweden
  - Clinic Stockholm
  etc...
 
Setting up the regions and various sites is simple in ServiceDesk Plus but we can not find a solution when trying to implement this in the request templates.
 
Question - How do we add "Region" as a field in the default request template for ServiceDesk Plus to first filter the Regions and then the Sites for the selected Region? (Similar to selecting first "Category", then "Subcategory" and then "Item" when categorizing a ticket)
For instance I first want to select "Region" France for it first to filter out only the French sites and then pick the "Site" Lyon - and not select Lyon in the full list of 280 Clinics/Sites.

                New to ADSelfService Plus?