To download or get attachments of tickets using an API, you'll typically need to interact with the API provided by the ticketing system or platform you're using. The specific steps and endpoints will vary depending on the ticketing system you're working with.

Hi 

Technically every attachment sent with the initial request can be found in the ticket GET API request like this: domain.freshdesk.com/api/v2/tickets/1

You can also view all conversations including attachments using domain.freshdesk.com/api/v2/tickets/1?include=conversations.

It’s not a download and it’s probably not applicable to downloading attachments in bulk, but maybe this could help in some way.