Practice
So you've got the basics here of how to use your pick and how to fret a note on the fretboard. You will have already done more than this just through experimenting and playing around with your guitar, the idea now is to spend a bit of time practicing the exercises here and then go back to the playing around that you were doing before but this time you'll know how to hold your pick and you'll be starting to develop an approach with your left hand. In future lessons you'll learn more specific skills to make your movements accurate and efficient but just playing around now won't hurt so go for it.
Divide your practice session in to three and spend equal time:
- Doing the exercises.
- Practicing the song
- Playing around and exploring to see what you can find.