This achievement requires that you watch eight movies. In order to watch a movie, you must have a TV. Purchase one from the Home Store if you do not (there is one in the tutorial house). There is no level requirement, so go ahead and knock this out right away. Select the TV with a free Sim and begin a movie. It will take 1.5 to 2 hours to complete, depending on the type of TV. Once the movie is complete, that counts as one. You can have multiple Sims watching a movie together, but it will still only count once towards this achievement. If you have a few TVs, have each Sim watching their own.