You can try with Autocomplete Widget.
Hope this helps.
This widget does something similar: https://appstore.home.mendix.com/link/app/106803/Tiruven-Inc/Textbox-with-Suggestions
It is maybe outdated and needs some changes to work in your Mendix version, but this could give you a starting point
We are using textbox-with-Suggestons , but we are unable to save the data after selecting from dropdown.