How to return thenable JS object with change event?

I want to auto-fill field belong event change at create screen. I called API from event to get data. But event can’t return thenable object, so I can’t fill data to form of record.
Which way can I do that?
Thank so much

Hello @Tan,

Welcome to the Kintone Developer Forum & thank you for posting your question!

To better help you out, please provide more information regarding your current situation, question, and desired outcome.

I am not exactly sure what you are asking for.
But here are some API docs that might be related to your question:

Thank you for your time,

Hello Genji,
i resolved my problem with xmlHttp request.

thank you answer my question