How to download images uploaded in the forms via webhooks integrations?

How to download images uploaded in the forms via webhooks integrations?

We have created a form that will be taking photo uploads and signatures.
and we integrated a webhook integration to our backend server on each form submission. Which is working fine and we can receive data in webhook API. But the images uploaded come with a simple name in it.
How do we download those images to our site? Are there any API endpoints from Zoho to download those images uploaded in forms?

and also signature is not able to get in webhook integration.