try searching on https://libgen.is/ for the textbook, i think i found it on there
i think i used the textbook a bit for examples of code but you could probably just google it instead
the unit basically just teaches you Excel VBA and how to automate things in Excel
If you are on Android you can use this app https://play.google.com/store/apps/details?id=com.kevilondo.referencer it's fast and easy to use