Hi Harri,
Here is our
guide on ads for the API. It details all the supported ad types. You can use the API to create any of these ad types that you feel comfortable. The API is recommended to those that have dedicated engineering resources.
You can create all of the
criteria that you mentioned such as keywords, placements and audiences. If you have no experience with the API, please see this
table and see if it is suitable for you. You may want to use simpler approaches such as
Google Ads Scripts if you don't have much coding experience.
Let me know if you have any other questions.
Cheers,
Anthony
Google Ads API Team

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