Import the video in olive video editor. Play it in media viewer to check it.
Drag and drop the video on timeline. Play it in sequence viewer.
Right click on the video on timeline. Click on Link / unlink option to separate video & audio.
Click on the audio and hit delete key on keyboard. Play the video in sequence viewer to check it.
Import new track in project. Drag and drop it below video track on timeline. Play the video in sequence viewer.