The fast quick easiest way is to use this link below, the result will generate a special link for you to use. The manual way is to add the “&t=” then the minutes and seconds you would like to start playing. For instant, a youtube video link https://www.youtube.com/watch?v=blahblahblah&t=2m6s notice the &t=2m6s that will start the video at 2 minutes and 6 seconds on the video.
https://youtubetime.com/