NEED HELP WITH COMMENT COMMANDS

(RPG MAKER 2003)

Hello,
I'm trying to set up plugins for my game (namely https://rpgmaker.net/engines/rt2k3/utilities/61/?post=825018#post825018 for allowing the user to switch between windowed and fullscreen modes on the main screen).

However, I've never delved into using comment commands and I am unsure on where to put the ones listed so the effects ACTUALLY take place. (Should they be in Common Event with auto set as the trigger? Should they be on the first map of the game? What about the settings?)

Thank you.