Why does nobody talk about deep fakes in fix-it videos?

I was putting up some shelves in my living room and watched a video for tips. The person in it showed perfect cuts and smooth moves, like it was all real. But when I tried, my shelves were crooked and the brackets did not fit. I learned later the video was a deep fake, made to look like a pro but it was all fake. Now I am stuck with a messed up wall and trying to learn how to tell real videos from fakes. It is so annoying because you waste time and money on bad advice. How can we know what is true when fakes are everywhere? I just want to do simple home jobs without getting tricked.