copy and edit

Hi how are you?

I really want to add some notes to this lovely note collection but i'm just a little confused. I wanna to write my edition from the song of "king of the past" in this url: https://musescore.com/user/7012111/scores/5157568

I actually need to copy some parts of this piano sheet in order to add something else to it. (I download and install the app for writing notes)

could you please guide me how to just copy some part of that url?