Hi there,

This is a good question and the way Lisa plays the B major chord in this lesson: https://www.guitartricks.com/lesson.php?input=23478&s_id=1906

is correct.

She begins her strum with the F# note and that's okay. When playing chords, you don't have to start your strum with the root note, a lot of chords are like this. You have to remember that chords, at a very basic level are simply triads, or a set of three notes that are played together. Tlo create a B major triad, all you need are the three notes: B - D# - F#

When it comes to playing chords, your ears will most likely hear all three notes ring together, creating the chord tone.

The bigger difference is when you remove the root note B. If you take out that B note, it will not longer be a B major chord.

More advanced players, or experienced players do also play B major as a barre chord. The barre chord looks like this:

As you can see in the above graph, you can use your index finger (1st finger) to barre the entire second fret, and if you play it this way, you will begin your strum hitting the B note, if you strum from the low strings to the high strings. But again, I would not get hung up on where a strum begins, because even if you play this B major as a barre chord, if you do an upstroke, you'll be hitting the F# note on the high E string anyways.

Long story short: it doesn't matter where you start the strum, it only matters that you hit the three notes of the triad.

I hope that helps!

-Billy