More details: https://open.shopee.com/documents?module=63&type=2&id=51

1. Go to https://open.shopee.com
2. Sign in or sign up an account.
3. On the “Console” menu, click “Add Management” > “App List” to create an app.
   
4. Enter the required fields and click “Submit”.
   
5. After submit, you will see your app is in auditing. It may take some times to approve.
   
6. After your app is approved. You can get your Partner ID and Key.