Hello Anum,
Thank you for reaching out to us.
As for your 1st question, yes, Ad cost refer to your spend. As for your succeeding questions regarding the equivalent metrics, I'm afraid that our team can comment on this any further. You can reach out to the Product Team via this link instead for more details on this.
As an aside, you can also check on this mapping guide to map the concepts and naming conventions for reports in the Google Ads UI to the comparable AdWords API reports.
Regards,
 |
| Mark Kevin Albios |
| Google Ads API Team |
|
|
| |

ref:_00D1U1174p._5004Q2JFHvS:ref