how to generate shared link after uploading file with rest API in asp Core.

Yes, it is possible to generate a pre-signed URL for an object in AWS S3 through the REST API without adding the AWS S3 SDK as a dependency. One way to do this would be to use the AWS S3 REST API's "PutObject" or "GetObject" endpoint, along with the "X-Amz-Signature" header to sign the request using your AWS S3 access key and secret key. Once you have the pre-signed URL, you can share it with others to give them temporary access to the object. An example of how to generate a pre-signed URL using the AWS S3 REST API in C# without the AWS S3 SDK can be found in the AWS documentation. https://docs.aws.amazon.com/AmazonS3/latest/userguide/ShareObjectPreSignedURL.html