You can check the official Kotlin Multiplatform Template Gallery to take a look at the Multiplatform Library template. It's quite helpful and showcases the steps as outlined in the official documentation.
The template provides a "bare-bones project intended to quickly bootstrap a Kotlin Multiplatform library".

Lastly, if you want more compose-specific samples, you can check out the JetBrains Kotlin Library platform on https://klibs.io/?tags=Compose+UI to give you a better idea on how to structure yours.