In Libre base How do I make autofill happen on a form with a combo box?

Right now I have a form where I have the fields on the right and a combo box on the left when I select an option in the combo box it fills in the correct field but I want it to let me type in the field and pick an option from the combo box without having the click on the combo box.

How do I set it up so it will do autofill?