How to add values ​​to dropdown list in webform?

Question

Drupal

Hello, tell me please. There is such a task: there is already a "settings" menu item, and when we go to "settings", we need to make an interface for adding and deleting elements to the webform drop-down lists. It's just that in the form itself there are already 6 fields of the "List Items" type, and now you need to add elements to these fields. Can you please tell me how this can be done?