Hi @john john Pter ,Good days.
Unfortunately, SharePoint Online does not include any built‐in functionality to capture the client’s IP address when someone submits a list form. Power Apps also does not provide an OOTB function to return the IP. However, you can achieve your requirement by creating a custom solution (via a PCF control) that retrieves the IP address and writes it to the list.
Here is a post for your reference:
http://powerappsguide.com/blog/post/get-ip-address
Non-official, just for reference.
Hope it helps you.
Please do let us know if you have any further queries.
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