The command below can record screen video by ffmpeg on Windows.
ffmpeg -y -rtbufsize 100M -f gdigrab -framerate 30 -probesize 10M -draw_mouse 1 -i title="Task Manager" -c:v libx264 -r 30 -preset ultrafast -tune zerolatency -crf 25 -pix_fmt yuv420p "video output.mp4"