The chord E/B that is shown here contains the notes: B, E, G#. The root of the chord is E (The lowest sound - the bass - is B). The scale from which the chord is derived is Major, and the degrees of the scale are: 1, 3, 5.
To play the chord E/B shown above, place your fingers as follows:
On string number 5, on fret number 2 with finger number 2 (middle finger)
On string number 4, on fret number 2 with finger number 3 (ring finger)
On string number 3, on fret number 1 with finger number 1 (index finger)
On string number 2, on fret number 0 (open string)
On string number 1 (the thinnest), on fret number 0 (open string)
Start strumming from string number 5 (notice not to play string 6).