I actually recently decided to make a CLI blackjack game as well! It was a fun exercise, although my focus was more on the visuals since I enjoy making ascii graphics.
Obviously you know what they meant, no need to expect newcomers to have a complete knowledge of what exactly linux is. As far as someone coming from windows or OSX is aware of, “linux” is the alternative.
You can’t get around not having a VPN if you don’t want your ISP to know you are doing. Sounds like you might not have a complete idea of what exactly a VPN is doing and why you need one.