Don't get discouraged. The quickest answer I can give is, #1, have somebody knowledgable look at your guitar to make sure it's set up correctly. #2 is look for a teacher--and don't think you have to commit to a whole raft of lessons right away. Just ask for one lesson and see how it goes.
Buzzing could be caused by not fingering close enough behind the fret, or not enough pressure, but could easily be caused by the setup or fretwork being out-of-whack on the guitar. Also, other strings shouldn't buzz unless you are also picking them along with the intended string, so that's a separate problem. Why would other strings buzz if you're not picking them? There are so many things to look at besides your fingering hand (your left, if you're a righty, or vice-versa).
In other words, just don't look at one aspect, like the angle of your fingers to the string. Guitarists constantly have to change their joint angles anyway, depending on what they're doing; crossing to other strings on the same fret, making full bar chords, or playing just two strings in a "mini-bar" a-la Chuck Berry, for example. If you're feeling held up in one aspect, shift to working on something else, like picking exercises, maybe crossing strings in different patterns. You'll be surprised how much it helps to "take a vacation" and come back to something. Good luck