If I Were a Boy by Beyonce is in Em at 100 beats per minute and runs 3:26 across 63 bars. It uses 5 chords — Em7, C, G, D, Am. The chord diagram changes as the song plays and the words light up as they are sung, so you can strum and sing along without reading ahead.
Want the melody line note by note? If I Were a Boy guitar melody tab.