Practice mode can be accessed by selecting a song, and then selecting this icon:
In the Practice view of a song, you can see the chords that are used within the song, as well as an overview of lyrics (if they're available) and the chord changes. Lyric lines will highlight as the song plays back so you can keep your place. This is a great mode to use if you want to get an overview of the full song and its structure, or maybe as a reference when you're playing with others.
We're constantly working to improve Fender Songs, so if you have some ideas about how we could make Practice mode better, please reach out to us!