If you don't know sports and you're 18, don't worry! There are many ways to get involved. First, you could try watching a few sports games, either on TV or in person. This will give you an idea of the different sports and their rules. You could also try joining a team as a beginner. Most sports have beginner leagues or teams that you can join to start learning the basics. Finally, you could look into sports-related activities, such as running, yoga, or even playing video games. Whatever you choose, there are plenty of ways to get involved and learn about sports.