In Settings, Phone line, pick Every call goes to CallsIn, and CallsIn rings me first and choose how long it rings. Calls to your CallsIn number ring your cell. You hear "press 1 to answer" so your voicemail never takes the call. If you don't pick up, the caller gets the AI or the text-back.
You can also call customers from your CallsIn number so they see your business number, not your cell.