While I'm working the computer a video appears automatically. How do I get rid of it? I click the X and that does it temporarily but I want it gone permanently.

What video? Any more info?

When I am doing my email or on the Internet out of the blue a video will appear. They are about people, dogs etc. doing goofy things. There's nothing to identify it, therefore have no way of uninstalling it. Is very annoying. It started a couple of days ago and have no idea why or how it happened.

Sounds like some form of adware. I would install malwarebytes from Malwarebytes.org and see if that helps take care of it.

As mentioned above, install and run malwarebytes