Get URL https: and Not the gs: Firebase

You can obtain the download link in the following way

 storageRef.child("tu_direccion_a_la_foto/blkbl....jpg").getDownloadUrl().addOnSuccessListener(new OnSuccessListener<Uri>() {
        @Override
        public void onSuccess(Uri uri) {
            // Conseguimos el enlace de descarga
            Uri downloadUri = taskSnapshot.getMetadata().getDownloadUrl();
            String urlFoto = downloadUri.toString(); //El enlace a la foto hecho string
        }
    }).addOnFailureListener(new OnFailureListener() {
        @Override
        public void onFailure(@NonNull Exception exception) {
            // Manejamos algun error
        }
    });

I'm assuming that you want to find these files by putting them in Firebase Storage, remember that .child("tu_direccion_a_la_foto/blkbl....jpg") is the path where that photo is stored in Firebase Storage. If you want to get the link of the photo uploaded and store it in Firebase Database, I recommend you to follow this answer.

For more information on how to obtain the download link, follow this LINK