Hello @MichaelHan-MSFT ,
You could use JQuery to auto Populating textboxes/form in SharePoint online/13/16.
Please follow these steps:
1.Create two customized SharePoint Lists, named "Employee Table" and "ET.1". As shown below figure:
2.Go to ET.1 List, click new item link to jump to NewForm.aspx
>> click "Edit page"
3.Click "Add a Web Part" >> click "Media and Content" folder, and then add "Script Editor" web part
4.On the "Script Editor" web part, click "EDIT SNIPPET" >> on the Embed dialog box, paste the below script: The JQuery.txt
5.When you create new items , you will find the following effects
Thanks,
Echo Du
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