NateLosesGames no this would jusg be entering a command.
A script is a set of commands in a file (I'm making it simple here).
What you need is to open a notepad, paste what he sent and save it as a .gsc file then compile it and put the compiled script in the right folder.
This documentation can help you https://plutonium.pw/docs/modding/loading-mods/#t6