Hello Min,
From what I understand, you are looking to link a manager account to another manager account. Please refer to
this guide on how to link the accounts which will be helpful to get started. You will be able to locate the MCC ID of the user account by logging into the Google Ads account and you will be able to find the customer ID on the top right corner as mentioned in
this guide. Could you please take a look and let us know if you encounter any issues?
Thanks,
Bharani, Google Ads API Team

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