How to declare and set buttons in a live wallpaper using Kotlin and Android Studio

I'm trying to work my way into Kotlin, and AndroidStudio 4.01. I've got several questions in this regard.

1.) Suppose my application is supposed to be a live wallpaper (with some settings that you can call). This live wallpaper is supposed to be updated every second (by a service?) How am I to declare this (service?) within the manifest?

2.) How can my app get access to the wallpaper? E. g. how can I place a button onto the wallpaper that leads to the settings window?

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