I have been doing youtube for a while now and was just wondering when going to create a thumbnail can I use any background I want from google images as long as its not sexual or misleading?.
As far as I know, you can just as long as you include a URL of the image's website in your description. That's what I and many friends have been doing and we haven't been collared about anything.
You could also blur the background too in Photoshop or paint.net, just to make sure that you don't get approached.
No problem in using something from google. As for the website link that is not needed. Just look up a wallpaper you find fits and your done. Because i am not a artist i use that method too for over a year and always worked fine