Do I need to put an ad-ID here or something else?
There's gonna be 3 Advert ID:
1: The first one is your game Advert ID. Which AdMob will be giving in the earliest section. Don't copy this.
2: Interstitial advert ID. Copy this and put into interstitial advert ID ONLY
3: Banner advert ID. Copy this and put into banner advert ID ONLY
Hope this is what you are asking...