Hey Beth. For the E chord, you pluck the low E string as the first note.
If ever you are in doubt, the first note that doesn’t have a minus sign on the chord chart, will be the 1st note of that chord.
So, since we start the strum from the top (the low/deep pitched strings), you need to look from the left to the right of the chord chart. So for G, there are no minus symbols, which means the low E will be your first note. For Am7, the low E has a minus symbol, which means don’t play it. The next string has a dot, which means you don’t have a finger on it, but you will play it. So that string becomes the 1st note of the chord.
I hope that helps make more sense of it so you are able to decipher that issue in the future. Let me know if you have any other questions!
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