Check out example codes for "paypal api get access token". It will help you in understanding the concepts better.

Code Example 1

curl -v https://api.sandbox.paypal.com/v1/oauth2/token \
   -H "Accept: application/json" \
   -H "Accept-Language: en_US" \
   -u "client_id:secret" \
   -d "grant_type=client_credentials"copy

Code Example 2

{
  "scope": "scope",
  "access_token": "Access-Token",
  "token_type": "Bearer",
  "app_id": "APP-80W284485P519543T",
  "expires_in": 31349,
  "nonce": "nonce"
}copy

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