Hi Larissa, have you learned the notes of the fretboard? That would be a good place to start. Then learning scale patterns like major and minor would really help you to know where to go when looking at a piece of music. I’m sure there are other things to say about this (I’m only learning myself), so perhaps Mark or one of the other more experienced guitarists here could add to this? Mark McKenzie’s theory course was very helpful I found.
Defiantly look up some Music Theory. I watched 3 – video on youtube. It didn’t come close to sinking in for me but I got a start. Something I did not realize is Jamorama has the lessons in printable form or Tabs. You can watch the video then circle back and practice with the Tabs. Start from the beginning and save them or print them out.
I’m not there yet on notes on the fretboard yet either, but I can read sheet music (slowly). It’s kinda funny how sheet music and guitar is almost mutually exclusive… guitarists have invented their own notation to avoid having to read sheet music… that was part of what attracted me to guitar after taking violin lessons years ago.
There are some great music theory videos on YouTube.. I watched a bunch of them by a guy called “Lypur” — he’s a pianist, but he’s a good teacher.