@NoahVancouver I've moved your post to the Sims 3 Mac section.
When you say the game is frozen, do you get any error message at all? If you see something about a problem in connecting to EA servers, please try this:
https://answers.ea.com/t5/Technical-Issues-Mac/Sims-3-quot-Important-Message-There-is-a-problem-connecting-to/m-p/8317259#M5856
Otherwise, please start by doing a clean uninstall of Sims 3, removing all the hidden library files that don't get deleted during the normal uninstall process. Here's how:
https://bluebellflora.com/how-to-do-a-clean-uninstall-and-reinstall-on-a-mac/
Install the base game only, and run the Super Patch (digital download version) to manually patch the game to 1.67.
https://bluebellflora.com/sims-3-manual-super-patch-for-mac-1-67/
Launch the game again, and let me know whether it works. If you get the error about connecting to EA servers, try the workaround in the first link. If you get an unknown error, or some other kind of error (let me know what), please list 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