Re: Unable to start due to missing game data - not Mac

@myid123321  As a test, please try playing in a clean user folder.  Move the entire Sims 4 folder out of Documents > Electronic Arts and onto your desktop, and when you launch the game, if it launches, a clean folder will spawn with no content.  (Your saves and other content will be intact in the folder you moved but temporarily not read by the game.)  Don't add anything to the new folder yet; just let me know whether you can get far enough to start a new save and play in live mode for a bit.

If you get the same error, please try repairing the game in Steam.  Open your game library, right-click on the Sims 4 icon, select Properties > Local files > Verify integrity of the game files.

By the way, your computer is running out of storage.  It's not dire yet, but the strange thing is that your internal SSD is a 256 GB model, yet Windows only sees 90 GB of total space on the disk.  Have you partitioned the drive or done anything else that would explain this discrepancy?  If so, then you know what you're doing; otherwise, this is something to be addressed.