re: “Step 1: Open the System Settings on your Mac and go to Desktop & Dock.” — This may or may not be correct, depending on which version of the Mac OS you are running. For example, in Mojave, it’s under General settings (which makes more sense, actually, since the default browser setting has nothing to do with the dock or the desktop). You could have specified that this is how it is done in the OS you were demonstrating. But a more universal suggestion would be to type “browser” into the Settings/Preferences search field, and it will show you where the setting is in your OS.