Find the video you want to use, in this case we will be using a YouTube video called akward forest vlog from a YouTuber known as YuB. Then click on the video.
Click on the arrow icon encircled in gray
Click on the circle with 2 angle brackets labled Embed
Check the boxes Show player controls and Start at 0:00 (You can change when the video starts playing). Copy the code highlited in blue.
Paste the code you copied into your HTML file and your video will apear fully functioning (I have already done so, the portion of code with a gray dot next to it is what you copied)