SOLVED: after Upgrading my iMac 2019 the microfon did not work - iMac Intel 21.5" Retina 4K Display 2019 - iFixit
How to Connect an External Microphone to an IMac - Instructables
AccLoo USB Microphone for Computer, USB Gaming Microphone Plug & Play Desktop Omnidirectional Condenser PC Mic with Mute Button & LED Indicator, Compatible with iMac PC Laptop Windows Computer : Amazon.ae: Computers