Start with this movie if you want to watch the show.

The show takes place years after the movie and replaces the main actors (although some of the original movie actors do end up in the show from time to time!)

Interesting to compare this movie to 10,000 BC, also by Emmerich. I think 10,000 BC is a slightly superior movie. I wish Stargate had gone a different direcion after the first 30 minutes and been a lot more “serious,” like Contact or Arrival.