@Lovelyshawn The issue here may be the processor and RAM, or it may be your hard drive, particularly if you've installed Sims 4 on an HDD. Your graphics card is still fast enough to handle ultra graphics settings, and the GPU isn't as involved in loading times as the other components. (That's not to say it makes no difference, only that the 1060 is unlikely to be the limiting factor at any point in the loading process.)
Your processor could only be upgraded to another 2nd- or 3rd-gen Intel Core processor, with the i7-3770K being the most powerful option in that category. This is a limitation of the motherboard. A newer CPU would mean a newer board and new RAM, and at that point, you might as well build a new computer. If you want to go that route, even if you're reusing a couple of components, let me know.
You might be able to find a used i7-3770K for a relatively cheap price. It looks like it's going for around $60 on Ebay, and Craigslist or Facebook Marketplace might have a cheaper offer, albeit with more risk. But I'm not sure it's worth investing even that given the relatively small performance improvement. Perhaps more relevantly, this computer is old enough that the other components might not hold up for much longer, so this may be a good time to look into a new build. Still, it's your choice. A faster CPU and some new thermal paste could make enough of a difference to be worth the investment, and your hardware might last a few more years, depending on the luck of the draw.
I don't know what speed your RAM is, but your processor and motherboard will only support DDR3, which can't go above a certain speed that is relatively slow by modern standards. Still, if your current modules are running at a slow speed even for DDR3, upgrading to the fastest kit available might be worth the price. You should be able to see the speed in the Task Manager.
If you do have Sims 4 installed on an HDD, then installing an SSD would make a significant difference. I doubt your motherboard has an M.2 slot, but a SATA SSD uses the same type of port as an HDD, and it would be more than fast enough to remove this as a potential bottleneck. Plus, the drive could be reused in a future build, so it wouldn't be a waste of money no matter when you replaced this computer. I don't know where you live, but this is a good option in the U.S. in either 500 GB or 1 TB form:
https://www.amazon.com/dp/B07G3KGYZQ
If you have more questions, please feel free to keep asking.
