@Jasmine8394 If you installed Windows via Bootcamp, Sims 3 would run just as it does on a typical Windows PC. A number of us have done this over the years, with generally good results. Of course, if your hardware is weak for the game in macOS, it will still be weak in Windows, but the problem won't be the operating system,
The game typically does not run as well in Parallels. One reason is that both Windows and macOS run at the same time, so weaker hardware might not be able to effectively handle both OSs plus the game at the same time; this is less of an issue on the more high-end Macs. The other issue is that the graphics card drivers installed by Parallels are not great, and there's no getting around it. However, installing Parallels will require less space overall than a Bootcamp partition, since both OSs can share free storage. So this is a better option for some people.
If you'd like help setting up a Windows install on your Mac, please start a new thread, as this one is quite old. Please include the full specs of your Mac, as described here:
https://answers.ea.com/t5/Technical-Issues-Mac/READ-FIRST-Sims-3-Mac-Help-Guides-and-Troubleshooting/m-p/4756624#M2878
Please also click the Storage tab on the About This Mac screen, and list your free storage.
