Dropdown with User Generated Input

I am trying to build a dropdown menu that utilizes user generated input as the options and saves the choice to a dataset. I know I can use preset data to do this, but is there any way to feed the database that my dropdown is reading from live data to present?

just connect the dropdown to a data collection, some ideas here.

So I understand how to do that, but I would like to populate the dropdown itself with data collected in an earlier form. In this case, I have a user enter two words into a user input text box prior and now I want them to have the option of selecting either one.