Problem on Accessing Authorization code(OAuth 2 ) Api call

Hello, I have a query regarding the Access token.I am using the NopCommerce api as a demo project for testing purpose.When I logged in as a client user i got my client id and client secret.The followings are -
ClientId- 0e08a338-d5b8-4d92-997e-b677d8f28fc8
Client Secret- da5d26a4-bea6-4cbe-815d-f0ebb4839b93
I was trying to get the access token through Restlet while trying this, it is asking for Authorization Code.For this I used the following url and parameters-
redirect url-https://ecommerce.knacklive.com ,
auth url- https://ecommerce.knacklive.com/OAuth/authorize
access token url- https://ecommerce.knacklive.com/api/token
In Header-
Accept-application/json , Content_Type- application/x-www-form-urlencoded
In query parameter-
client_id-0e08a338-d5b8-4d92-997e-b677d8f28fc8
client_secret-da5d26a4-bea6-4cbe-815d-f0ebb4839b93
response type- code
But I am getting error 302
Can you explain what is the proper way to get authorization code and access token?

if you're willing to get logged in through external auth.. like google and facebook than you must provide the exact redirect link of login e.g
https://www.example.in/signin-facebook