I use NoPhoneSpam. This app allows recognizing incoming calls and filtering based on some rules. I allow only calls from my contacts but there are also other rules. When someone else calls you get a notification.
Developer says:
NoPhoneSpam is NOT intended as a feature-rich call-spam fighting app, but as a
replacement for Android’s missing call blocking feature. If you have Android 6+,
you don’t need this app, because call blocking should be supported natively!
Since most people have a higher than Android 5, I am wondering what benefits you see still using this app. What can’t be managed by the OS?
It works, but without access to the full Orange number database = for callers not in your contacts, the app does not show a name, but anyway highlights if it is an unwanted or telemarketing number (or nothing if it considers the number as approved = it was not previously classified as unwanted / telemarketing).
I cannot help with the configuration, I had it in a business phone with another OS.