Figure out what file type your video is and download it. The file will either be .mp4, .ogg, or .webm. After downloading it imput the code like this
<.source src="file.mp4" type="video/mpeg".> <./video.>
(When doing the actual code, remove the periods next to the brackets)
When you have the video you can adjust the height and width with these:
<.video width="320px" height="240px".>
(When doing the actual code, remove the periods next to the brackets)
First you go to youtube and select you video like so
Next you click share and after a small tab popps up you click embed.
Finally you click copy and paste it to your html page.