Find signed JWT, bearer token and x-request-id values for extract API

Hi,

I am a newbie to Adobe Extract API.

I am trying to use the extract API in postman. For this, I have downloaded the postman collection file from the URL: https://documentcloud.adobe.com/document-services/index.html

Now, I am trying to replace the variables in the file, such as client_id, client_secret, etc.

I have the client id and client secret but unable to get the following variables  "Signed JWT", "Bearer token" and "x-request-id".

Request you to let me know the steps to generate these variable values.