Microsoft Windows [Version 10.0.19045.6396]
(c) Microsoft Corporation. All rights reserved.

C:\Users\Old Gamer>cd downloads

C:\Users\Old Gamer\Downloads>cd video

C:\Users\Old Gamer\Downloads\Video>ffmpeg -i video.mp4 -c:v libvpx-vp9 -b:v 4M -crf 18 -c:a libopus -b:a 192k output.webm