Hi Hao Xi,
Thank you for reaching out to us. I see that you want to get the creation and and termination date for your campaigns. In the
campaign report, you can query the
campaign.start_date and
campaign.end_date, as well as having the same attributes for the
campaign object. The
change_status's last_change_date_time field is when the campaign or ad group last had a changed applied to it. Let me know if you have further questions.
Thank you,
Bryan, Google Ads API Team

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