Guitar string buzz sounds terrible!
If you've never heard guitar string buzz before, it sounds like this:
What is happening? In this example, the string(s) I had my finger on was deliberately not touching the fret fully. This causes a rattling sound between the fret and the string.
Some guitars have fret buzz problems, all over the neck. Does it sound like like you are making mistakes all over the neck without trying, regardless of how much you are squeezing the guitar? If so, the guitar might be at fault.
One way of fixing buzzes is to try fixing your technique first. Here's a pointer for you: Try to get your fingers as close to the fret without going over, like I do on this G chord:
Fixing guitar string buzz: Bring it to a guitar technician
Of course, not all technical suggestions for how to play guitar will help, especially in the case of buzzes. Sometimes, it's a problem with the guitar you are playing. How do you fix it? The easiest way of fixing guitar string buzz is by bringing it to a professional, a guitar technician.
Why bring it to a pro? Fret buzz can be a difficult problem to isolate. It takes some experience to become skillful at setting up guitars so that they have no string buzz at all. Guitar techs have that experience, and if you're a beginner you don't (yet). My personal feeling is that it's best for you to take a fret-buzzy guitar to an experienced tech instead of fiddling with it on your own.
What if you want to set up a guitar on your own? Well, it's not impossible. Consider that it will take you some time to learn.
My suggestion is to do a lot of research about the entire guitar set-up process before you attempt it. That, and I sincerely hope you don't rely on one website's advice on how to do it. After all, not everyone knows what's going on.
Finally, expect that you'll be working on your guitar for at least a couple of hours. If you don't have that sort of patience, let it go and just bring it to a pro. They'll fix the problem for you in a fraction of the amount of time.