Dropdown List that autofills with custom text option

Hello,

Two part question.  First, is it possible to have a dropdown box that will autofill a word as I type it, but if needed allow me to enter a custom text?  The only options I have found is to either have the custom text option selected at which point the dropdown won't autofill or I can have the autofill function but can only choose the items within the list. 

I have a form with multiple dropdown boxes that have numerous names added to them.  The majority of the time a name from the list will be chosen but on rare occasions I will need to enter a custom name. 

Second part, is there a way to have the autofill option work past just the first letter?  Having numerous names many of them have the same first letter so it would be nice for autofill to work past the first letter. 

I am using current version of Adobe Acrobat Pro DC.  Thanks much for any help.

V/R,

Lee