Playing notes: The term allegro means to play fast, but you should always practice slowly and carefully at first, then gradually build up speed. Two other very common tempo indications are andante - a slow, easy walking pace, and moderato - a moderate pace.
In bar 3 the first note (8) is played on the third string (at the 4th fret), as indicated by # A number in a circle always indicates a string number, not a fingering.
| (line 4) means to return to the beginning (D.C. stand for Da Capo, which means "the lead") and play through to fine (finish) which, in this case is at the end of the second line.