Press the flag, then use the up and down arrow keys to control the dragon. The buildings are not obstacles. Try to collect the strawberries, and get as many points as possible. There is no way to lose, so you can play as much as you want. The score instantly resets when you press the flag.
I followed a Scratch tutorial, and added, changed, and tweaked a few things. Enjoy! :) Thank you Scratch team for helping me get started with your video.