How to display existing provinces and cities in the address when modifying the link using the provinces and cities written in Ajax

The provinces and cities written in Ajax are linked. how to display the links between provinces and cities in the address when the address is changed using Ajax? the default links are displayed in all provinces and cities when the address is added, --Select---but how can I select the province and city in the drop-down menu of the province and city by default when the change is made? [The province in the drop-down menu is to take it out of the database and save it in an array variable, and pay the variable to the drop-down box]


Js code: