The steps to be followed for creating and configuring a Google API Console project depends on the type of OAuth 2.0 authorization scenario you are building in your application. Choose the authorization scenario you are building for; this guide will be customized based on your choice.
You need a Google API Console project for creating OAuth 2.0 credentials, and enabling the Google Ads API for your app.
The credentials are needed for the authentication and authorization of Google Ads users by Google servers. These credentials let you generate OAuth tokens to be used in calls to the API.
Although you can use a single developer token for multiple projects, each project can use only a single developer token.
Select or create a Google API Console project
Follow the instructions to create a project. Enabling billing for your project is optional. If you have billing enabled, select a billing account for the new project. There is no charge for using the Google Ads API, but there is a quota on the total number of Cloud projects.
Enable the Google Ads API in your project
To enable the Google Ads API in your project, follow these steps:
Open the API Library in the Google API Console. If prompted, select your project or create a new one. The API Library lists all available APIs, grouped by product family and popularity.
Use search to find the Google Ads API if it isn't visible in the list.
Select the Google Ads API, then click the Enable button.
Create a service account and key
Start by creating a service account and credentials. Next, create credentials for the service account. Download the service account key in JSON format and note the service account ID and email.