Sims 4 low fps on GTX 1660 ti

@Kerolajn1003  You're right, your CPU cores' temperatures should not be hitting 100º C here.  I'd hope they would never go above 90 or maybe 95 even at full load, but they should certainly be a lot lower with the CPU load shown in your screenshot.  And charging the battery shouldn't make a meaningful difference either: laptops are supposed to be able to run at max performance while plugged in.

It's possible, even with a relatively new laptop, that dust is blocking one of the vents or even a fan.  Omens are fairly easy to disassemble—you shouldn't need more than a small phillips head screwdriver—and taking off the bottom cover will let you visually inspect the fans and vents.  For the fans, even if you don't see anything amiss, spin each one manually to see whether it can move freely without slowing too quickly or catching on anything.  If you find dust anywhere, blow it out with compressed air; using suction can sometimes loosen or dislodge a smaller component.

Running in high performance mode will of course add to the load on your CPU and GPU but shouldn't be a problem on a gaming laptop.  If you want a good compromise though, try enabling vertical sync either within the game's graphics options or in the Nvidia Control Panel.  You can also use the CP to set the max fps to 60 either for Sims 4 (TS4_x64.exe) or overall.  Since your screen can't display higher fps than that, you won't notice a difference, and fewer frames means lower workloads for your components.

Still, like I said, you shouldn't be seeing temperatures like this, and an fps limit only disguises the problem, it doesn't solve anything.