Just press the flag! You can also do it in turbo mode (shift+press the flag) if you want to see how it turns out without waiting. No ads unless you worked hard on it and it's a genuinely good project. The thing that's making the lines is actually a teeny tiny version of the bug you see on the thumbnail, but without the pencil!
I'm basically new to scratch and this is one of my first projects! All art and code by me! Music: Rainy Day Games by The Green Orbs