Flow of Presigned URL

I think a little bit of context could be useful to help you. I'm guessing that you are using S3 Presigned URLs to serve static content in a web/mobile app? If so, usually your backend will call (through the AWS SDK) the S3 API to create the presigned URL, and it will deliver that URL to your frontend. The frontend will then call that URL to download the content protected by the presigned URL.

If that wasn't your case, feel free to add more context in order to help you!