How to prevent outside callers from going straight to voicemail in Focus Mode on iPhone 12?

Hello my question is about iPhone focus mode.

When I place my iPhone in focus mode it does not ring when someone calls me. This is great! however, how can I still use focus mode but prevent outside callers from going straight to voicemail? I don't want to send callers straight to voicemail when my iPhone is in focus mode because I do not want to notify everyone that I'm in focus mode. I use different profiles at different times and do not (at least not always) want folks knowing I'm silencing their calls.

If the person in my contacts list texts me, I'm okay with focus mode sharing with iMessage, but how can I disable focus mode sharing with the phone app? I'm not sure how to achieve this result without turning off focus mode (which would defeat the purpose of using focus mode.)

I already know how to allow specific callers depending on the "focus mode" profile I set up and enable. That is NOT what I am asking about. I am asking how to ensure the outside caller hears the phone ring when they call me but my phone does not ring.

My desired phone behavior: when in focus mode, my iphone does not ring but callers hear the phone ring on their end instead of going straight to voicemail.

Thank you! (I have an iPhone 12, and it is up to date on iOS 26.5.2)

[Re-Titled by Moderator]

Original Title: Focus Mode: Caller hears ringing instead of being sent to voicemail, but my iPhone STAYS silent