Can somebody help me with Go2RTC and ffmpeg?

[Barabba]

Hi, I'm truggling trying to find help, on Github group no answer and no instructions how to passa arguments to ffmpeg.
I need to capture screen and send with go2rtc but it doesn't work with their instructions, so I would like to try with ffmpeg

With this command it works on my PC:

ffmpeg -f gdigrab -framerate 30 -i desktop c:log\output.mkv

I've tried to format it for go2rtc like this but it doesn't work:

streams:
  test: ffmpeg:-f gdigrab -framerate 30 -i desktop
ffmpeg:
  bin: c:\ffmpeg.exe

How is correct? SOmebody can please write the right config with ffmpeg?
or direct, if it's possible like the author says with this instructions, but I can't make it work:

You can turn the browser of any PC or mobile into an IP-camera with support video and two way audio. Or even broadcast your PC screen:

    Create empty stream in the go2rtc.yaml
    Go to go2rtc WebUI
    Open links page for you stream
    Select camera+microphone or display+speaker option
    Open webrtc local page (your go2rtc should work over HTTPS!) or share link via WebTorrent technology (work over HTTPS by default)

Thank you!