Let's see the steps to how to embed a video into your website from Youtube.
First: After opening the video on youtube; click on share. 
Second: Click on Embed. 
Third: Copy the text.

Fifth: Paste the text into the body. 
Sixth: Save your website as ".html" document. You can give whatever name you want. 
Seventh: Click on the website you created and you can watch the Youtube video on your website now. 