Do I need to register with Google Ad Manager to use the Admob Banner component? I already have an Admod account and will publish my first app created on Kodular to Google Play.
No they both are completely separate entities, that being said you should register for an admob account and integrate the ad unit id in the respective AdMob components.
Also note that you need approval to show ads when your app is not published to play store. However When you are Publishing your app to Play Store you don’t need any approval from Kodular as Google already reviews your app for compliance.
That means ads will only be showing when downloaded from Play Store if you are not requesting approval.