Oh sorry I didn't read it carefully. No. Apple won't provide guides for how to integrate ads in your app because it might differs from providers to providers. Your ad provider will provide such guidance. If not, just search tutorials made by others and I'm sure there will be many.

Yeah just find a provider you would like to use. The provider you use will provide their APIs to allow you test and deploy ads. If you don't know where to start, AdMob is not a bad choice IMO.