any help in starting out in Networking?

I will be taking an IT course later this year, and then I will take a course in Networking.

However the only problem is I only ever studied IT as a general subject, never had subjects like computer studies and whatnot.

Are there any good youtube channels, PDF's, or programs I can download so I can get a better idea? My boyfriend talked about a program which helps you build a network IRL but he doesn't know the name

Any help would be greatly appreciated as I am really eager to learn <3