I am not getting information via the MuseScore 4 Tutorial on adjusting page size

I am new to MuseScore Program. I have been waiting for about a month and a half for the MuseScore 4 Program to come out before I started to use it.
The MuseScore 4 Program is out now, and I have begun to do the tutorials on how to use it. I started this morning. The thing is, it introduces itself by saying that you can Change the size of the MuseScore page by hitting the Control key at the top of the Window. It is shown on the Program Tutorial to be present... but I have tried to turn on my MuseScore 4 Program on my Computer and no such Control -- Window size button is active. Thus, I don't know how I am supposed to make my Sheet Music file Bigger or Smaller.
I want to be able to adjust my Sheet Music size to fit into what I am seeking to do with the generation of composition of new songs.
Why does your Tutorial for MuseScore 4 NOT cover the same product as that which has been downloaded?
I need this to work! I have begun to write music on MuseScore 4, and it seems to be working out well. I just need to learn, as a Novice, how to add in the criteria to make Divine music. It is a problem if the Tutorial does NOT match the program on my computer. How do I fix it?