The Full E Minor Chord
Let's learn to play our E minor chord using all six strings.
Locate the A string, place your middle finger in the 2nd fret. Remember to be right up against the fret. Locate the D string, place your ring finger in the 2nd fret. So we have our two fretted notes and now you're free to strum all six strings with your pick.
It's quite possible that your E minor chord may have sounded poorly because your fretting fingers are accidentally touching and muting the surrounding strings. If that happened, then try to see if you can adjust your fingers so all the strings are ringing. It helps to pick them one at at time with your pick. Or at least a few at a time.
Sometimes the issue will be the angle with which your fingertips are hitting the fretboard. Try moving your thumb up and down behind the neck. Sometimes when you move it down towards the floor a little bit this angle will naturally get better.
Don't stress too much about getting this chord perfect if it's tricky right now. There'll be plenty of opportunities to work on that later.
For our example I'll count to 4 and then we'll strum this chord 8 times. After that we'll strum the chord and let it ring. If you feel inclined to experiment with the rhythm or playing the notes one a time, it's more than okay.