The game won't use my GPU

@Evergreenium  Your dxdiag contains a few errors related to the Nvidia graphics driver, so the place to start is with a clean uninstall and reinstall of the driver.

https://crinrict.com/blog/2019/02/clean-re-install-of-graphics-drivers-with-display-driver-uninstaller-ddu.html

Grab a fresh copy of the newest Nvidia driver:

https://www.nvidia.com/Download/driverResults.aspx/184717/en-us

The Intel graphics driver is also quite old, so it's a good idea to update that too.  You can get the newest one here:

https://www.intel.com/content/www/us/en/products/sku/97185/intel-core-i77700hq-processor-6m-cache-up-to-3-80-ghz/downloads.html

The order of operations here is to download both drivers, take your computer offline, run DDU to remove the Nvidia driver, restart, install the new Intel driver, restart, and install the Nvidia driver, then restart before trying to play.  You'll also need to redo any settings in the Nvidia Control Panel.

I followed all the steps but now it's even worse than before. For the first time in my life I got the error 'Cannot load game.' when loading up a household. It took extremely long for my game to start-up (normally takes 1min, now it was 5min). Still not using my GPU but now it's using 100% of my disk! My disk is running at 23MB/s and I've never EVER had sims using my disk. What is going on??

I've also added a new dxdiag after all the updates.

@Evergreenium  The game should definitely not be maxing out your disk, except perhaps when it's loading.  Even then, 23 MB/s seems a bit low.  Are you sure Sims 4 is maxing out the disk all by itself?  If there's something else running in the background that's hitting the disk at the same time, that would explain at least part of the issue.

Is your laptop plugged in while you play?  If not, please try that, and make sure it's actually showing the charging symbol: the laptop would likely throttle performance when running on battery, and it's easy for a cable to come loose or get bent the wrong way.

If that's not the problem, it's a good idea to make sure your Nvidia card is actually working properly, which means running a benchmark.  Please download the free 3DMark demo from Steam (there's a Download button to the right of the price for the full version) and run Time Spy.  You'll see a button to view your results in a browser window; please link me that page.  It shows your hardware info and your Steam username but nothing else identifying.