Even Wikipedia would be a good start: https://en.wikipedia.org/wiki/History_of_the_Internet

If you prefer video, watch the 1998 PBS piece Nerds 2.0.1: A Brief History of the Internet. I won't link to it because I'm not sure if the site is legit, but I just re-watched a few minutes of it and it's funny to look back at the hype in that era.

the internet for dummies is a start