An arpeggio is a chord played one note at a time. Arpeggios are often used by the left hand to accompany a melody played by the right hand. The following example demonstrates the chords Dm and C played as arpeggios.
A dot written after a quarter note indicates that you should hold the note for one and a half beats. A dotted quarter note is often followed by an eighth note.
Scarborough Fair is a folk music standard. The accompaniment in this arrangement consists of arpeggios of the chords Dm, C and F played by the left hand. Take it slowly at first and practice each hand separately if you need to.