How to curl with user ip not server ip in php

I have.

https://opsukrat.in/ip.php

This url

I need to curl with user ip not using server ip..
Please solve my problem..

$ch = curl_init();

curl_setopt($ch, CURLOPT_URL, "https://opsukrat.in/ip.php");

curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);

curl_setopt($ch, CURLOPT_FOLLOWLOCATION, TRUE);

$ip = curl_exec($ch);

curl_close($ch);

The short answer to your question is: you can't. You cannot route traffic to a third party so that the traffic is coming from a random user's IP address. However, depending on what you're specifically trying to do (more on that at the bottom), you may have some options.

1. On some endpoints, you can add --header "X-Forwarded-For: XXX.XXX.XXX.XXX" where you pass the original requester's IP address. Some environments look for that header in the CURL request and may pass it for specific purposes on their end. In the case of "https://opsukrat.in/ip.php" this won't work as they are only looking at the actual requesting IP address.
2. If you don't care about getting a response back from the endpoint, there are ways of spoofing your IP address. This requires some advanced networking set-up (you can't do it just with CURL to my knowledge) and you can't get any packets back... this can be used (generally maliciously) to send POST/DELETE/PATCH calls to a third-party with a spoofed IP address. In your case, you need the response, so that's a no-go (and I can't think of a legitimate case where you'd want to do this).

> Correction on this second suggestion: As Barmar pointed out in the comments, this wouldn't work for TCP traffic in any case because - before the actual request is transmitted - the sender would have to be able to respond to a SYN-ACK packet from the server, which it couldn't do because the IP was spoofed. For HTTP(S) traffic this approach would just never work. Leaving this as part of the answer as it may be
> illuminating.

3. If this is for an intranet, or some other case where you know and can cooperate with the requesting users, you can have all participating users install proxies on their machines and you can use CURL's proxy functions to pass the curl request back to the requester's IP address (using $_SERVER['REMOTE_ADDR'] for the IP)... so you'd have the request flow back out through the user's proxy service from their own IP address. This is a ridiculous theoretical use-case/set-up but it's at least a technical possibility.

HOWEVER, based on what I'm seeing, you don't need a CURL request at all! Your entire code can be replaced this this:

$ip = $_SERVER['REMOTE_ADDR'];

And now you have your user's public IP address.