Lag/fps drops making the game unplayable

@Huiiie_07  Since your computer is using almost all of its installed memory, it's worth trying to play in a clean boot.  The idea here is that you shut down everything other than Windows-related services to free up as much RAM as possible.  Even if you don't want to play like this in general, find out whether it helps, and we can go from there.

https://support.microsoft.com/en-us/topic/how-to-perform-a-clean-boot-in-windows-da2f9573-6eec-00ad-2f8a-a97a1807f3dd

The one service to leave enabled is the EABackgroundService, which the EA App needs in order to run.  Disable the rest as described.

When you reboot your computer, go through the Task Manager's background processes list shutting down any service that doesn't absolutely need to be running, for example anything from MSI Afterburner to RGB software might still be enabled.  If you accidentally kill a critical process and it doesn't restart on its own, just reboot your computer again.

Don't open anything other than Sims 4 and the EA App while testing, not even a browser window.

The fans getting loud does suggest that this might be a temperature issue though.  If you want to find out, you'll need to do some hardware monitoring.  Please download hwinfo (it's free) from here:

https://www.hwinfo.com/download/

You don't need to install anything; just choose the Portable version, unzip it, and launch it from Downloads or wherever you like.  If you do want the full installer, be sure to click the button for hwinfo itself, not for lansweeper.

Restart your computer, open hwinfo, choose Sensors Only, and click the button that's a sheet of paper with a + to start logging.  Save the log file to your desktop for easy access.  Wait five minutes, then open Sims 4 and play for at least 20 minutes.  Don't alt-tab out of the game or run any other programs, aside from the EA App of course, while you're testing.  When you're done, click the same button to stop the logging.

Please upload the log to the third-party filesharing site of your choice (Google Drive, Dropbox, etc.) and link it for me.  Either leave it in .csv format or, if you're going to use OneDrive, create a .zip file, and don't open the log before uploading it, or else my log reader might not be able to interpret it.