Piracy

Hey everyone, I live in a dorm like apartment where my Internet plan is part of my contract. I have a monthly data limit which just isn't enough for me. Buying additional data is stupid expensive. I found out though that your used data is only calculated once you disconnect from the internet completely. So my idea is to get a small device that is constantly connected. I could use an Amazon echo / Google home, but I'm not comfortable with the idea of having one. Could I just hook up something like a raspberry pie to the Internet and how would I go about ensuring that it has a constant connection? Thanks for your time and sorry for the long post.