How to track when a new message appears in Amazon SQS?

Question

PHP

The essence of the problem is as follows.
1. User requests with data come to the site and are saved.
2. Keys to data are sent to one queue for all requests. (in my case it is Amazon SQS).
3. Next, the queue, when a message appears, should send them one by one for processing to another url.
Those. I need to process parallel user requests sequentially.
Is it possible for the queue, when adding a message, to send it to another URL that I will specify automatically?
Or is the only option to constantly monitor Amazon SQS?
Is such a scheme even possible on Amazon?
Maybe you can do something differently if it's not possible on amazon?