Will a CANON 35-80MM F4-5.6 lens fit the Canon Rebel XT?

I don't know much about the Canon Rebel XT, but I bought one at a yard sale that didn't come with a lens, so would this lens work for it?
Also if anyone knows any good youtube videos I should watch to learn more about this camera?

ANY Canon EF or EF-S lens will fit your Canon XT.

What lenses will not fit are Canon FD or FL lenses.

The things you need to learn are the fundamentals of photography and they are applicable to ANY fully adjustable camera whether it is a Canon, Nikon, Sinar, Pentax, Hasselblad or any other.

Here is a link that will show you how to balance ISO, shutter speed and lens aperture and another discusses how to compose compelling images.

Learning how to see light, is going to be up to you

If the mount t is EF or EF-S written on it, it will fit on your camera.

Yes it would. Bring your camera to the shop where the lens is sold and test it first before paying. Now if you're buying online, that would be a huge gamble.