I want to include ads to my app, but I initially selected the no ads option while registering my app.

When registering my app for the first time, in the Ads questionnaire, under the question "Does your app contains ads?" I selected the "No, my app does not contain ads" because initially I had no intension of adding ads to my app. But now I want to include ads to my app. Please what do I do?

I want to include ads to my app, but I initially selected the no ads option while registering my app.
 
 
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