How to do cascading dropdown in PowerApps?
Cascading Dropdown in PowerApps means one dropdown control value depends on the previous selection in a hierarchy, i.e., when a user picks an option from one dropdown control, the values filter in another Dropdown control.
How do I create a cascading drop down list?
In the same or in another spreadsheet, select a cell or several cells in which you want your primary drop-down list to appear. Go to the Data tab, click Data Validation and set up a drop-down list based on a named range in the usual way by selecting List under Allow and entering the range name in the Source box.