Can someone help me?

Can someone help me? I got lost doing a lab. The instructor used "vi" and I followed suit, then got stuck, then he told us to use "nano" instead in the commands but I never caught up. Also, the instructions on the left aren't clear to me, but I think I'm only supposed to type the stuff in the purple and green boxes. However, I can't "exit" this window. I feel really really dumb right now. 😢