Here is the link for a HubPages lesson on how to add a video.
You need to use the video capsule when you are making a hub.
Then click on youtube then search for a video that is suitable as some are better choices than others.
You will find lots of helpful advice in the HubPages learning centre the link for this is always at the bottom of the page.
You will also find that people have made hubs about this and other hub making topics if you do a search for them in the search box.