At the start. Before the first line, the letters: Greek has 24, and many of them look like ours.
You do not need to learn them all by heart now. Every step has the alphabet folded at the top, for when you forget one.
The 24 letters τὰ γράμματα
Tap a letter to see its name and hear how it sounded. marks the seven vowels: α ε η ι ο υ ω.
Six names you already know. Sound each one out, then clicktap it to check.