Need help: nano

I don’t know what to do after this and I also don’t know what Crrl + O means and stuff like that


You have to press 3 keyboard-keys a once
1st press tasto CTRL and tasto SHIFT ( keep pressed )
2nd the tasto o
You are now writing to a file
Answer the question with a tasto RETURN

i’m working with a macbook pro, azerty ,
when i type cmd + maj + o : nothing appears. I know that normaly it must bring me to terminal. but nothing happens.
PS : when i use iterm it works
what should i do ?
Help plz I want to validate my skills