How do you create a video with other video clips?

I have to find out how to make a video for youtube with other video clips for school. I have no idea how to.
Can you get clips off the internet and save them to your computer or something?
I am using Windows Movie Maker, by the way.
So please, I need to know how I am supposed to do this.

Thank you so so much!

-Alice
I dont know how to save the videos either. And could you maybe tell me the names of some sites that allow you to download video?

use windows movie maker and place the clips in order…
thats how i make my AMV

you can get clips from sites, but some of them wont let you because it is copyrighted..

good luck