Go to the “APIs & Services” → “Credentials” on the left sidebar.
Click the “Create credentials” dropdown button and select “OAuth client ID”.
Select the “Web application” as the Application type.
Fill in the required fields, such as the “Name of the client”.
Add your Authorized JavaScript origins (your web app’s domain) and Authorized redirect URIs (where users will be redirected to after successful authentication).
Click “Create” to generate the client credentials. Keep the “Client ID” and “Client Secret” as you’ll need these in your frontend and backend configurations.