is there a way to delete App Store and iCloud and start again?

You can certainly sign out of iCloud and sign back in with some other ID. Perhaps if you explain what has you so upset, someone can recommend an appropriate course of action.

You might also want to start with this article:

Manage your Apple ID account information - Apple Support

You stop using it. You drop the ipad from an existing apple id. You can change to a different apple id on your ipad. You cannot delete an apple id. You cannot transfer an app from one apple id to another.

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