If you want to get better at playing guitar parts, you might pick up a classical guitar primer or two... Reasonably simple pieces to play in standard musical notation (NOT Tab!), and these will teach you a lot about guitar voicings and techniques. And there are also a few that transcribe more modern styles like James Taylor, and the like (PLENTY of hard rock 'shredding' primers out there, but I doubt that's what you are after!).

Just be prepared to understand that it is VERY difficult to play convincing guitar with just one hand... The spread on guitar chords and lines is very wide. Simpler lines and 6th intervals will get you close, but full guitar chords often span two octaves - a simple E chord goes (from bottom to top) EBEG#BE, and picking patterns for folk and folk-rock can span even greater distances, as 'open' notes are used for drones at the low strings, and other strings are played higher up the neck...

Welcome to the wonderful, wacky world of guitar voicing... it's a whole different world to keyboard playing!