1. You dont need electric guitar or distortion to play power chords. Power chord is a style of playing intervals (two notes). YOu can play that on piano/acoustic/violin anything that supports two simulataneou notes.
2. That switch is supposed to change the pickups. One pickup they can keep at low output, so that it sounds clean, the other pickup they keep at high output, so that it gives distortion.
3. If you wanna play real distortion etc, your acoustic is not really meant for all that.
4. Master you playing technique on acoustic. You may get whole gamut of electric gear later, when you feel you are quite proficient.
You donít get what you deserve, you get what you negotiate.