How do I structure my particular application for third party API integration? [closed]

I am building a Go service that communicates with multiple third-party providers. This go-service act as an interface between these multiple providers and my internal applications consumes just one API from Go.

My application has the below structure now

• app
• config
• controllers
• dto
• exceptions
• providers - All external API calls to thrid-party happens here
• services - Business logic
• tests

I would have to integrate to over 10 third-party APIs and I am confused on how to keep the structs for JSON marshal and unmarshalling

What I was planning was

• dto
  • thirdparty1RequestStruct
  • thirdparty1ResponseStruct
  • thirdparty2RequestStruct
  • thirdparty2ResponseStruct ... and so on.

But when I have around 20 third parties APIs, there would be a lot of request-response struct and the directory will be too big from a readability perspective.

My question is

1. How exactly do we structure API response/request structs in Go?

2. Whats the best practice to be followed?

3. Is dto a right approach?