Unplugged Ballad (5274) is a slow country/folk backing track for guitar (or another soloist!) in E minor. There are two parts. The first part is based on the key of E minor. The keys E minor and G major are related, consist of the same tones and also have the same accidentals, namely 1 sharp. In the second part there is a trip to G major, but then it goes back to the original key via B7, the dominant of E minor.
Play along, follow the sequence of chords in real time, develop your own musical ideas! Have fun!